Keep cool all summer long with this effortless style.

 

Tousled WHY IT WORKS There's a reason why Lively revisits this pony again and again. "It feels like you're not trying too hard," says the star's hairstylist Jennifer Johnson. It's also red-carpet-ready: "When she's wearing a fancy dress, the hair softens it." Movement is key, so if your strands are poker-straight, Johnson says, wrap a few sections around a curling iron before pulling them back. EXPERT TIP Use dry shampoo to add texture at the roots, then tease lightly with a brush. Gather hair into a medium-height ponytail and secure with an elastic. Slide the elastic down slightly, then split the pony into two sections and pull apart to retighten, which tousles the crown. Wrap a section of hair around the base of the tail, covering the elastic. Secure with bobby pins. Use pomade on the tail to give it a piecey look. Video: How to Create the Perfect Ponytail>