TREND: Long-sleeve leopard-print dresses

WHO'S WEARING IT: Paris Hilton, Kim Kardashian, Michelle Trachtenberg

HOW TO WEAR IT: Last summer, we spotted colored leopard print in the form of minis, tops and even gowns. This season, it's all about the long-sleeve dress. Winterize the popular piece with black tights and accessories.

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TREND: Spiky studded heels

WHO'S WEARING IT: Lauren Conrad (Aldo), Katie Cassidy (Rock & Republic) and Kara DioGuardi (Rock & Republic)

HOW TO WEAR IT: The prickly pumps are all about classic in the front and rock 'n' roll in the back. Keep the spikes a showstopping surprise by wearing the shoes with a feminine mini.

Shop the steal 'n' splurge below! Then, keep reading to see how the stars styled the trend.

TREND: Textured skirts

WHO'S WEARING IT: Beyoncé and Alexis Bledel

HOW TO WEAR IT: From ruffled zippers and rosettes to croc print and fur, a textured skirt will give your look some visual interest. Just be sure to tuck a nonfussy top into the bottom—you don't need any more added volume on your figure. Wear simple yet sexy heels to elongate your gams.

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TREND: Leopard-print ankle boots

WHO'S WEARING IT: Rihanna, Kelly Rowland and Whitney Port

HOW TO WEAR IT: The fierce feline kicks will spice up fall's blacks and grays. For a look that's all about pure animal magnetism, wear the spotted shoes with a sexy black bodycon dress. Then, add a little splash of color with a purple clutch or yellow skinny belt.

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I want to try the over-the-knee boots trend without looking trashy. Any tips?
—Sara W., East Windsor, Conn.

There's no question that over-the-knee boots have a bad rep because of their association with streetwalkers and showgirls. But it's high time to dismiss all that, because if there's one trend to try this season, it's over-the-knee boots. Here are some tips and tricks to get a leg up on fall's hottest footwear fetish the right way.

TREND: Watercolor dresses

WHO'S WEARING IT: Alicia Keys (BCBG Max Azria), Leighton Meester (Louis Vuitton) and Thandie Newton (Matthew Williamson)

HOW TO WEAR IT: Watercolor dresses don't scream cold-weather chic. So winterize them with lots of black—black tights, black pumps, black bag, black jacket, black belt. Just think twice about wearing black socks with black shoes à la Leighton. That's one artistic statement not everyone will understand.

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TREND: Leather pencil skirts

WHO'S WEARING IT: Kim Kardashian, Kristin Cavallari and Audrey Tautou

HOW TO WEAR IT: Balance the leather with a sweet tucked-in top, like a lace turtleneck or ruffled blouse, and a nice pair of heels when rocking the trend at night. For a more casual look, pair it with a graphic tee and flats or black tights and booties.

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Meet the Parents star Teri Polo gave us a peek at her personal style during Kari Feinstein's Pre-Emmys Style Lounge...

Fashion Philosophy: I'm a jeans-and-T-shirt girl. I like True Religion, Joe's Jeans and Seven, and Hanes' plain white wifebeaters. I like fun jewelry. You can dress me up maybe once a year. I really love nice, clean lines. I don't like patterns. I like basic colors.

Fave Red Carpet Dress: I wore a pale cream dress to a Golden Globes afterparty years ago. It was the ultimate comfy yet elegant simple dress that I've worn.

Makeup Must-Have: I love Lauren Hutton's Face Disc. It has everything from cover-up to blush to lip gloss. The colors and textures are unbelievable!

Check out mystyle's Shop Her Style galleries to get the signature looks of stars like Rihanna, Sienna Miller, Lauren Conrad and first lady Michelle Obama!

TREND: Dresses with shoulder cutouts

WHO'S WEARING IT: Olivia Palermo, Diane Kruger and Claire Danes

HOW TO WEAR IT: The cutout trend may be dubbed the "cold shoulder," but the peekaboo effect is hot, hot, hot! Balance out the sexy style by opting for a dress in classic black. Any attention-stealing necklaces are banned!

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TREND: Tulip skirt dresses

WHO'S WEARING IT: Jessica Stroup (Charlotte Ronson), Penélope Cruz (RM by Roland Mouret) and Paula Patton (Jason Wu)

HOW TO WEAR IT: The part wrap dress, part toga will add curves to your bottom half, so be sure to have on heels to elongate your frame. This fall, we're going to pair a jewel-toned tulip skirt dress with black tights and pumps.

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TREND: Belted cardigan

WHO'S WEARING IT: Leighton Meester, Janet Jackson and Victoria Beckham

HOW TO WEAR IT: Cinching a slouchy cardi will not only make the casualwear look chic, it's a fantastic way to show off your shape, especially when you're wearing a patterned bottom layer. As for color, a caramel-hued belt will pop against fall's grays, while a classic black waistband oozes sophistication.

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True Blood star Anna Paquin gave us a peek at her personal style during LA Dogworks and Good Dog Animal Rescue's "A Night of Emotion"...

What She's Stylin': I think the dress is Tracy Reese. The tag is no longer inside. It's been in my closet forever. I like it! My shoes are by Jimmy Choo.

Fashion Philosophy: I mostly wear jeans, T-shirts, summer dresses, shorts and sandals. If I'm going out, I like to dress up.

Genius in a Bottle: I just started using Moroccan Oil's shampoo and conditioner. It's great for girls who dye their hair blond, like me. It actually makes your hair not look like it got sucked down a drain and then slapped on your head. It's nice!

Color Crave: I like a lot of black. The teenage goth girl in me is still peeking out every once in a while, but I'm branching out. I'm wearing navy blue tonight.

Check out mystyle's Shop Her Style galleries to get the signature looks of stars like Rihanna, Sienna Miller, Lauren Conrad and first lady Michelle Obama!

TREND: High-neck tie blouses

WHO'S WEARING IT: Hilary Duff and Marcia Cross

HOW TO WEAR IT: Wear the top with a pencil skirt or slacks to work for a classic look. Then take advantage of the conservative neckline by pairing it with leather leggings or a miniskirt outside of the office.

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TREND: Various incarnations of London-based designer Christopher Kane's black velvet-trim silk dress.

WHO'S WEARING IT: Freida Pinto, Whitney Port and Diane Kruger

HOW TO WEAR IT: Christopher Kane is the designer of the week with not one but three starlets having worn his distinctive frock recently—plus his TopShop line launches today! Wear the new It dress to a cocktail party with matching booties to complement the edgy design. Accessorize with simple earrings and a small clutch.

Shop the steal below at one-fifteenth (!) the price of the original.

TREND: Leather jackets

WHO'S WEARING IT: Michelle Trachtenberg, Jessica Lowndes (For Joseph), Nicky Hilton

HOW TO WEAR IT: Run with the tough-as-nails look by pairing a leather jacket with skinny jeans, a black top and a chain statement necklace—or go for a cool contrast by layering it over airy, feminine frocks.

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