Time flies when you're having fun and looking stylish! (Well, that's how it feels around the Who What Wear office anyway.) It seems like just yesterday we were writing about spring trends and making sure that you, dear readers, were equipped with all of the best warm-weather essentials, and now it's nearly fall! As such, we figure you're probably set as far as summer staples go, but it never hurts to have some additional suggestions about how to wear these key piecesÂ--right? Indeed! Fittingly enough, today's quartet of stylish celebs provides you with all the outfit ideas you need, as we're sure you'll see. So whether it's a print pant à la January Jones or Leighton Meester's nude-and-neutral palette that piques your interest, read on for some super-cute, easy-breezy, summer-style inspiration.

January Jones
As Mad Men's Betty Draper, January Jones is always perfectly coiffed and immaculately turned out in an obsession-worthy assortment of chic dresses, cigarette jeans, and ladylike heels. That look requires loads of grooming, so it's no wonder that Jones prefers more laidback styles for her off-duty hours. For example, in July the actress was snapped en route to the Gavert Atelier Hair Salon in Los Angeles wearing a delightfully relaxed ensemble, comprised of Topshop's Floral Printed Trousers ($80, 212.966.9555) with a white blouse she picked up from a boutique in Europe and Frye's Delphine Strappy Sandals ($128). To recreate this cute and comfy look, we suggest you pick up Heritage 1981's Flower Field PJ Pant ($10), Eli Tahari's Harlow Blouse ($244), and Wild Diva's Tanaya Sandals ($20); the combination is sure to capture Jones' bohemian spirit. Last, but certainly not least, finish your outfit with Rebecca Minkoff's Nikki Bag ($475), which looks quite similar to Jones' preferred purseÂ--Prada's Black Calf Leather Tote ($1750, available at select Prada boutiques)Â--but is only a third of the price!

Emmy Rossum
You obviously appreciate the simplicity of a great summer ensemble, which is why we received so many inquiries about a charming outfit Emmy Rossum recently wore. The actress was photographed late last month leaving the Apple store in Soho wearing Juicy Couture Victorian Lace Dress ($278), a perfect pick for a hot afternoon. Looking for thriftier alternatives? Don't miss Cooperative's Linen Dress ($48) or Alloy's Heidi Eyelet Dress ($35), both lovely lightweight options. Now, the best part of a white canvas is the fact that you can liven it up with colorful and cool accents. Rossum did just that with bright red Marais USA Espadrille Wedges ($88, 800.282.2200), and then topped off her sweet look with Gerard Darel's Mini Sac Hobo Flat Lima from the S/S 10 collection. While her exact bag is no longer available, try Ecote's Square Perforated Suede and Canvas Satchel ($78) for an affordable in-stock option.

Leighton Meester
Although the season premiere of Gossip Girl is still a month awayÂ--September 13th to be exact!Â--Leighton Meester is already showing us some seriously desirable looks. She was spotted on the show's set a few weeks ago wearing a military-chic ensemble, comprised of a nude Helmut Lang button-down shirt with AG Adriano Goldschmied's Skinny Cargos ($198), Derek Lam's Wine Powder Calf Odessa Shoes ($790, 212.966.1616), and a pair of 3.1 Phillip Lim sunglasses. Sadly, Meester's exact shirt is totally sold out, but there are plenty of light-colored shirt options out there, like Gap's Utility Tunic Top ($55). If you need some army green slim cargos, we suggest grabbing the AG style when it hits stores later this month, or try Alloy's Stretch Cargo Skinny Pants ($40) now. Then all you need is a pair of Carlos by Carlos Santana Tamingo Sandals ($99) and ASOS' Purple Top Flash Visor Sunglasses ($17) to finalize your Meester-inspired look!

Katie Holmes
The double denim look has been quite popular for months now, but few ladies have worn it in a standout way. Happily we have one to add to that list: Katie Holmes. The actressÂ--seen here arriving at a heliport in New York City last monthÂ--created her enviable ensemble by pairing Madewell's Chambray Workshirt ($68) with a flared pair of MiH's Marrakesh Jeans ($190). While Holmes' denim-on-denim combo is quite casual, the yummy mummy stepped things up a notch with couple of chic totes, namely Lanvin's Crinkled Calf Skin Happy Bag ($2175, 212.753.7300) and a Hermes Birkin. If you'd like to equip yourself with an equally cool outfit, pair Mossimo Supply Co.'s Denim Shirt ($20) in Moon Shine Wash with Express' Rerock Jeans ($80) in Medium Wash, then conclude your ensemble with The Limited's Ladylike Ribbon Bag ($50) for a reasonably priced Lanvin lookalike!Â--Jessica Baker

Photo of January Jones, courtesy of WENN; Photo of Emmy Rossum, courtesy of Bauer Griffin; Photo of Leighton Meester, courtesy of Splash, Photo of Katie Holmes, courtesy of PCN
EXPLORE: What Was She Wearing, Topshop, Prada, Madewell, Lanvin, Juicy Couture, Hermes, Helmut Lang, Derek Lam, AG Adriano Goldschmied, MiH, Leighton Meester, Katie Holmes, January Jones, Emmy Rossum


See More Stories