Maybe you think that a black blazer will just be good on a corporate look. Only just a perfect office attire. But the truth is, a great blazer can polish your look instantly. According to Coulter, the most flattering cut skims your arms so they look slim and nips in at the waist. Stick to two buttons and one vent. And hem it if need be: "The jacket should end at the bottom of your hip bones-just an inch longer, and it can look a little bulky," she says. And don't forget comfort: "It should look tailored but feel quite soft when you handle it-stiff fabric is the worst." Coulter likes wool for day crepe for night. And buy a stand-alone blazer rather than one half of a suit: "They're designed to be worn with a variety of pieces, so the proportions are usually better."

Three Ways To Wear It

1. Sweetly does it. "I love a blazer over a feminine chiffon dress," says stylist Nicole Chavez. "It's a nice way to mix those two looks-something soft against something structured." So a color pastel dress is definitely look awesome when partnered with plain colored blazer. It will look elegant and professional.

2. After 8. "I'm a big fan of leather pants worn with a black wool blazer," says Coulter, who likes the ones from Elizabeth and James and Isabel Marant. "I'd wear them with black pointy heels and chunky gold jewelry."

3. Showing leg. A classic blazer makes shorts look more sophisticated. "I like shorts that are tailored and neat," says stylist Lawren Howeel, who suggests wearing them with a tucked-in silk blouse. "The look is pretty, but the silhouette is sharp."