Fall's Faux Bob

When Marion Cotillard wore the summer's most-anticipated collection-Raf Simons' debut haute couture for the house of Dior-to the London premiere of The Dark Knight Rises, she also tried one of the season's most popular hairstyles. The faux bob-long hair teased, pulled back, and pinned at the neck-was refined by stylists like Orlando Pita at Oscar de la Renta and Derek Lam, Serge Normant at L'Wren Scott, and Odile Gilbert at Rodarte during the fall collections earlier this year and is the perfect transitional look to try now. Robert Vetica, the stylist behind Cotillard's wavy version, jokes, "Don't try this at home!" but offers a few tips on how-to if you insist (which we do). If you can, start with slightly dirty hair. "Wave the hair with a ¾-inch curling iron around the perimeter of the head," Vetica says. Make sure you start each curl at the root to guarantee texture at the crown. "After I put the loose curl and wave into her hair, I gently worked in Moroccanoil Hydrating Styling Cream ($34) to secure the bounce," he says. "It offers the shine and manageability needed to achieve this look."

Grab a clear elastic and gather the hair into a loose ponytail. "Start folding at the nape of neck," Vetica says. "As you fold, pin pieces underneath. Gently shape and craft your 'bob' and pin, leaving the front pieces loose for softness."

Vetica used Moroccanoil's Luminous Hair Spray ($18) in Strong Hold to "really anchor the hairstyle" but, he says, "the hair shouldn't appear shapeless or plastic, it should be voluminous and have a little bit of movement." Don't forget to pack a few bobby pins for the road-wispy is good, but you don't want the ends falling out halfway through the night.