Lloyd Boston, Stacy London and Charla Krupp

Does a miniskirt still look cute after 30? Can you still wear white after Labor Day? The rules of fashion are ever-changing—and they only seem to get more complicated as we age. Three experts are here to show you exactly how to dress in your 30s, 40s, 50s and beyond—all while staying trend-conscious yet age-appropriate.

Lloyd Boston, author of Before You Put That On, says the number one mistake women make is shopping by size, not by fit. "They're married to an 8 but the 10 starts fitting a little better," he says. "Go ahead and get the 10 and cut the number out. Get the clothes that fit, not the number you want to be and your clothes will look so much sexier."

Stacy London, host of TLC's Fashionably Late and What Not to Wear, says women who are overly concerned with trends make the biggest fashion faux pas. "There are three things always you should consider—your body type, your age and your lifestyle. And that's how you decide what trends are going to work for you. Not every trend works for every person."

Charla Krupp, author of How Not to Look Old, wants women to stop forgoing style for comfort. "I think women in America are so hung up on comfort, they walk around in clothes like they're going to the gym," she says. "If you dress well, you will get people to sit up and take notice."

Kathy before and after her makeover

Although Kathy is now 35 years old, she has found it difficult to transition out of her teenage wardrobe. "I like wild and crazy things you find in the juniors department," Kathy says. Her closet is filled with tank tops, miniskirts and cropped jackets—and what she doesn't have, she borrows from her daughter! "I don't want to wear old lady frumpy clothes, but I'm afraid that sometimes I don't always look age appropriate," she says.

Stacy shows Kathy that she can dress for her 30s without losing any style. This Doma patent leather jacket from Saks Fifth Avenue is a bold statement piece that Stacy says is perfect for a 30-something who wants to look casual but cool. At $595, the jacket has a steep price tag—but Stacy says its traditional shape makes it a keeper. "It's an investment piece, you'll be able to wear it for a long time," she says.

To flatter Kathy's petite frame, Stacy gave her Citizen of Humanity straight leg jeans paired with a figure-hugging Moschino knit top also from Saks Fifth Avenue. "You want to do a piece that's close to the body if you're a petite," Stacy says.

Kathy's 40s and 50/60s look

Want an older spin on Kathy's new look? Stacy found this great outfit for a woman in her 40s from Saks Fifth Avenue. She helps her pull off patent leather in a great flat boot by Stuart Weitzman paired with a beautiful cashmere sweater dress. She says the handbag doesn't always have to match the shoes. "That's a lot of patent on a little person," she says. "Or even when you're taller, you just want one signature piece."

For a woman in her 50s and 60s, Stacy brings a touch of patent leather into this outfit from Saks Fifth Avenue with an Yves Saint Laurent frame bag. "Just touches of patent is the way to do it," she says. "As you age, less is more." Instead, the main focus is on top with a great print and detailed pattern.

Cenell before and after her makeover

With her wardrobe staples consisting of baggy sweats, tired jeans and old-fashioned dresses, you might not guess that Cenell once competed in the Mrs. Ohio beauty pageant. "Between work and my kids, I worry that I've let myself go," Cenell says. To get this 30-something mom back in style, Lloyd took her out of her sweats and into new clothes that show off her knock-out figure. "She looks like she's in her 20s now!" Lloyd says.

Lloyd gave Cenell her age-defying look with a trend-setting metallic party dress from Saks Fifth Avenue by Marc by Marc Jacobs. "Metallics bring out that inner shine," Lloyd says. Cenell will also be able to get mileage out of her dress by dressing it up or down. "She can put this on over her favorite pair of dark jeans and do a girls' night out or [pair it with] sexy boots or heels and take it to a candlelight dinner with her man," Lloyd says.

Cenell's 40s and 50/60s look

Lloyd shows us that women of any age can pull off the season's hottest trends when it's done the right way. He modifies the metallic trend for a woman in her 40s with a subtly shimmering sweater set from Saks Fifth Avenue. The look is cooled down with cream pants and a cream bag that Lloyd says women should not be afraid to wear. "Ladies, wear your creams and whites straight through the fall and winter. Those rules are gone." As long as the fabric is season-appropriate, Lloyd says to go for it.

In your 50s and 60s, Lloyd says you can still wear the trends when they are done in the very best fabrics, like this soft leather jacket and gorgeous lace skirt from Saks Fifth Avenue. "Make sure the fabric is so perfect," Lloyd says.

Kimberley before and after her makeover

After having four children, 38-year-old Kimberly says she's frustrated with how her clothes fit over her ever-increasing midsection. "When I wear fitted tops or shirts, I just feel like it's hugging my fat and I don't know what to do about it," she says. "I don't really think I'm old enough to wear old ladies' jeans, but I don't like my butt hanging out of junior jeans."

Charla doesn't want to dress Kimberly in old lady jeans either! Instead, she teaches Kimberly a few tricks to conceal her problem areas. Starting with what you can't see, Charla gives Kimberly a shaper called Lipo in a Box (www.lipoinabox.com). "It's high-waisted and it goes down to a mid-thigh biker short. The reason I love this piece is it doesn't have a bra so you can wear the absolute best bra that you can buy and not just settle for the one that's in the shaper," Charla says.

Kimberly is wearing Robert Rodriguez wide leg pants from Nordstrom that Charla says are a great shape for many women. "They have extra space in the thigh area where we all need it. It's a comfortable pant compared to the skinny pant from last season where every ripple of cellulite showed." The pants also have a high rise, which Charla says is more flattering than a low rise. "It makes her look long, lean and powerful." Kimberly's new look is complete with a patent leather belt from Nordstrom to cinch in her waist.

Kimberly's 40s and 50/60s look

Following the wide-leg trend, Charla dresses the model in her 40s in black wide-leg trousers and a short jacket with a pop of color underneath, all from Saks Fifth Avenue. She then continues the trend for a woman in her 50s and beyond. "The older you are, the slimmer the wide leg pant," Charla says. Another trick to wearing wide-leg pants is making sure you have the proper shoes. "The wider the leg, the chunkier the shoe," she says. "Don't wear a sexy stiletto with that."

She recommends that a woman in her 50s or 60s wear a beautiful blouse like this one from Nordstrom by Oscar de la Renta. "It is the answer to I Feel Bad About My Neck. Wear this blouse—it brings attention to your face."

Goldie's before and after

Goldie is 44 years old and has admirably kept off a 65-pound weight loss for the past two years. Now she needs help learning how to dress her new body. "I still am under the illusion that I don't have a waist," she says. Her unflattering clothes are also making Goldie look older—she was once mistaken as her daughter's grandmother! "I have to tell you, that was a real blow," she says.

Lloyd says that there was one thing about Goldie's style that he didn't want to change. "She was never afraid of color," he says. To give Goldie's style an update, Lloyd dressed her in jewel tones. "Jewel tones, ladies, work on every skin tone," he says. He chose a Norma Kamali dress from Nordstrom in a jersey fabric to flatter Goldie's figure. "That's going to cling where she wants it and give forgiveness where she doesn't."

Goldie's emerald green bag goes with Lloyd's jewel-tone trend, complementing the colors in the outfit without matching them. "That matchy-matchy bag and shoe thing will put you 10 decades behind," Lloyd says.

Tina before and after her makeover

Tina is approaching 40 and is afraid she has lost her sense of style along the way. "As a result of throwing yourself into the role of mom with two young kids, you sometimes lose a little bit of yourself—your style," Tina says. Unfortunately, her high-waisted tapered jeans and high-tops sneakers that she's held onto since the 1980s aren't doing her any fashion favors.

Charla gives Tina's time-warped look a major overhaul by bringing her up-to-date with the latest trends. "This is an example of the hot trend called chunky knit," Charla says. Her gray sweater from Nordstrom over a stripped Missoni dress and brown tights by DKNY are warm yet stylish. "You can be comfortable and still be chic," she says.

Tina's style wasn't the only thing that needed a makeover. "Oprah, she only had one bra and it was a sports bra," Charla says. "So the first thing we did when we got to Nordstrom? We had her fitted. We got her girls up there!"

Tina's 30s and 50/60s look

Charla says that women in their 30s can wear a chunky knit and still look sexy. Charla created a more revealing look for her 30-something model with slim pants and a form-fitting shirt underneath her sweater, all from Neiman Marcus. "The younger you are, the more you can reveal," she says.

For an older woman, Charla chose something less revealing but just as stylish from Saks Fifth Avenue. "When you are in your 60s, you can wear a chunkier knit that's a little slimmer and more flattering," she says. "Putting it with kicky boots makes it pop and makes it edgy."

Susan's new look for the gym

Forty-nine-year-old Susan is looking for something more flattering to wear to her aerobic dance classes. "I feel intimidated working out next to young girls who have those great bodies and their cute little outfits," she says. "I feel frumpy and old in my oversized T-shirt and boring gym shorts."

Lloyd's answer for Susan is a chocolate brown workout ensemble from lululemon athletica paired with brown and pink Nike sneakers from Nordstrom. "It's sculpted around her body and it's chocolate brown, so it's going to be slimming without wearing morbid black," he says. "We did a shot of blush underneath. It's a halter style, so it's going to lift [the girls] up where they belong. And when it's time to work out, you want to reveal a little more as you get toned."

If Susan needs to run errands or catch a flight, Lloyd says she can dress up the outfit by replacing the jacket with a nice cardigan in a matching color and swapping out the sneakers with ballet flats. Lloyd chooses a sweater he found at Nordstrom. "Sometimes you only have five seconds. You can't go home and change," he says. "This is a quick way to do it if you're in a pinch."

Linda before and after her makeover

Mike turned his 51-year-old mom, Linda, into the fashion police for a wardrobe update! Among his mom's top fashion offenses, he says, are a black, muumuu-shaped dress with orange flowers, a blue and black number that evokes Star Trek uniforms, and what he calls her "traffic sign orange" dress.

Linda says she thinks her clothes are age-appropriate, timeless and classic. But her son disagrees! "My mom likes to think that because her clothes still fit after 25 years, that means they're still in style," Mike says.

The experts are on Mike's side. "Old clothes equal old look," Charla says. To give Linda a timelessly sophisticated look, Charla dresses her in a Zack Posen black pencil skirt paired with a Tesori printed top, brown leather belt from W. Kleinberg and Cole Haan boots, all from Nordstrom. "It's a great look for women in their 50s because you put it on and it's like a shaper. It gives you that va-va-va-voom booty, and it really is great for the hips and the waist," Charla says. "It's a very ladylike look. I dare you to put on a pencil skirt and not feel like a woman."

"I'm blown away," Linda says. "I just feel beautiful."

Even Mike approves of his mom's new look! "She looks great," he says.

Cindy before and after her makeover

Cindy, a 52-year-old yoga instructor, loves to show off her amazing body in miniskirts and fishnet tights—but she's not sure how much skin is too much. "My question is, how to dress in a modern way that looks hip—it's edgy, it's fun, but it's age-appropriate?" she asks.

Lloyd says the key for Cindy is to wear clothes that emphasize the silhouette, not the skin. He dresses Cindy in an outfit from Nordstrom, complete with a plaid cape by Jones of New York, cream pants by Theory, a Valette cream turtleneck and Stuart Weitzman peep-toe metallic shoes. "That's the body you work for with yoga, and you show it off with body-skimming clothes," he says. "Her body looks incredible, and the cape floats around everything."

Capes for the 30s and 40s

Lloyd says the cape is a flattering look for women of all ages. "Remember, if you're fuller on the top, ladies, you can hide it with a cape and you can do slimmer on the bottom," Lloyd says. "You don't want full things on the bottom."

For the 30s look, Lloyd chooses a bright yellow poncho-slash-cape piece with knee-length shorts and tights, all from Nordstrom. "You can belt it in and define your waist or let it out if you had to do it," he says.

Lloyd suggests that a woman in her 40s wear a cape like this one from Saks Fifth Avenue adorned with toggles, a cute metallic skirt and dark tights from Spanx.

Mamie before and after her makeover

Mamie recently celebrated her 61st birthday—but she doesn't dress like the stereotypical 61-year-old. "I love to wear my skirts short. I wear tight jeans. I wear push-up bras. The majority of the time, they look good on me," she says. "Is it too much? Do you think it's something that a lady over 60 should wear?"

Stacy says Mamie is a fiery lady—but she needs to tone down her wardrobe a little. "She felt very comfortable in her skin, so we didn't want to take that away from her completely," Stacy says.

To preserve Mamie's fire and sexiness, Stacy chooses to give her a "ladylike dress." Mamie's new look includes a Carmen Marc Valvo red dress and leopard velvet shawl by Ilana Wolf, both from Saks Fifth Avenue, and Stuart Weitzman gold strappy sandals, a gold rhinestone cuff and Nadri chandelier earrings from Nordstrom. "We're using lap pleats that make a V. We're also raising the visual center of gravity by creating a cummerbund that's higher than her natural waistline," Stacy says. "So when you look at her, she looks like she has longer legs. She's got this great-fitting silhouette."

'Ladylike dresses' for the 30s and 40s

Stacy says a woman in her 30s wearing a "ladylike dress" similar to Mamie's can afford to show some more skin. From Saks Fifth Avenue she chooses a plaid dress by Nanette Lepore with a sweetheart silhouette that reveals a little cleavage and shoes by Dolce & Gabbana. "This kind of plaid is a neutral pattern," Stacy says. "In other words, you can pair this with a bright color if you wanted to. Or from far away, it's going to read as a solid, so you can add another pattern in if you wanted to do a pattern."

For a woman in her 40s, Stacy chooses a ladylike dress ensemble by 3.1 Philip Lim, available at Nordstrom, that emphasizes the waist while camouflaging problem areas. "In your 40s, that's when things start to spread, right? Your hips, your arms start to sag. The girls go south," Stacy says. "The idea is that this is still a flattering silhouette, still waist-conscious."

The main thing for a woman of any age to focus on when buying a "ladylike dress," Stacy says, is the waist. "This is a trend that you're going to see season and season again," Stacy says. "The idea here is that you want to show off your curves. If you pay attention to your waistline, you will always have a flattering silhouette. That is what works for women as long as the girls are up there where they should be."

Stacy's classic look for every age

Women of any age can wear classic, sophisticated looks, and Stacy, Lloyd and Charla have assembled their favorites. Stacy's look includes a black sheath dress, a frame bag and a camel hair coat. "This look is timeless. There is no shoulder pad involved, and there is no long jacket. A camel hair coat is like a trench for winter. … It will never go out of style. It works on every skin tone," Stacy says. "This perfect sheath dress, you can raise the visual center of gravity again with a belt if you need to, and that raises the eyeline a little bit if you've got a little bit of a tummy. And fishnets? Classic."

The luxury version of this look—which costs a total of $5,550—includes a Burberry coat for $725, an Armani dress for $1,170, Miu Miu patent peep-toe shoes for $450, a belt for $85 and a Bottega Veneta bag for $3,120, all from Saks Fifth Avenue.

For a more affordable version at a total of $794, Nordstrom carries a camel hair coat from Michael by Michael Kors for $268, a Nine West black dress for $109, a belt for $30, Enzo Angiolini peep-toe shoes for $89 and a Monsac croc frame bag for $298.

"You can find these trends at any price point, and they are investment pieces," Stacy says. "Lloyd was saying before, buy your coat before you buy anything else. If you have a great coat, a great bag and a great shoe, you can pop all your old clothes into a new season."

Lloyd's timeless look includes a black trench and animal print skirt.

Lloyd says women should feel hot and sexy at any age—he suggests an animal print piece to do the trick.

His luxury look from Saks Fifth Avenue costs a total of just under $6,000, including a Jean Paul Gaultier black trench for $2,995, paired with a white blouse for $800, gold flats from Chanel for $630, an $1,150 handbag and a skinny belt for $85. "Ladies, get a crisp, white shirt every season. Don't let the yellow ones come into your life. You have fresh ones out of your closet like tissues," Lloyd says. To finish off the look, Lloyd adds a knee-length leopard print skirt for $325. "I've seen ladies in their 60s work them better than women in their 20s, because they've been around forever," he says. "If you do it right at the knee, you can do it with a fun gold flat."

Women can get a similar look for around $355, Lloyd says. He finds a black trench at Express for $128 and pairs it with a crisp white shirt for $39.50 and a leopard skirt for $59.50, adding a $28 belt at the waist for a flattering fit. "You can belt just about any waist. It's about how you wear it. It's not about function," he says. Lloyd finishes off the look with a $30 bag and $70 shoes.

No matter what your age, you've got to work it! "This is a timeless, classic look, and when you pull this together, you want to make sure you walk into the room like you mean it," he says. "When you come in apologizing like, 'Oh, does this look okay? I'm not sure if this works. Does this work?' People attack you mentally. When you come in like, 'I own the room,' you look as good as this diva."

Charla emphasizes the importance of sexy jeans.

Charla's classic look hinges on one very basic item—a good pair of jeans. "Nothing will take 10 years off like a pair of sexy jeans," Charla says. "They are the best piece of clothing I have. … But the key is the fit. They have to fit you exactly right."

Charla's luxury look from Saks Fifth Avenue includes a pair of Paige Premium Denim jeans for $179, a Saks sweater for $198, a black leather jacket by Vince for $595, Jimmy Choo sandals for $490 and R.J. Graziano jewelry for $325, costing a total of $1,787.

For a less expensive look at $376, Charla chooses $59.50 Express jeans, an Express sweater for $39.50, a $168 leather jacket from Banana Republic, shoes from Nine West for $69 and Rachel Jewelry from Nordstrom for $40.

"The trick here is you want a really sexy, high-as-you-can-stand-it metallic sandal that's really strappy because it gives you a fun evening look," Charla says. "You can go to a party in this. You can go out to dinner with this. This is just a great look that everyone should have in her closet. And you should update it each season with the jacket of the moment. This short crop jacket that goes kind of trapeze is the jacket this season."

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