A fitted jacket can jazz up jeans in seconds and bring sharp, clean lines to loose dresses. "You'll instantly look put together," says stylist Cher Coulter, who suggests pushing up sleeves for a cool effect. As for the color, consider navy the new...well, you know. "It's less common than black and much more feminine," she adds.
Polyester jacket, Express, $88; express.com.Read MoreLess