Style 101: Tips for Every Woman

The Fabric: A collared white shirt works best in poplin or twill, which give structure and aren't too sheer.

Keira Knightley's wore her oxford man-sized—could it also be a wardrobe staple for boyfriend Rupert Friend?

GET KEIRA'S LOOK ONLINE NOW
Donna Karan shirt, $487; at net-a-porter.com.