First, find the basic shape of your face: Oval Faces are narrower than they are long, with a rounded jawline. Square Faces are roughly as wide as they are long, with a strong, square jawline. Heart-Shaped Faces are roughly as wide as they are long, with a jawline that comes to a point at the chin. Round Faces are roughly as wide as they are long, with a rounded jawline. Then, check out which frames are right for you: Both round and oval faces naturally narrow at the top and bottom, so large, oversized frames actually have the effect of making your face look leaner, because they sit right over the widest point. To buy: For a similar product: $395; nordstrom.com. Good news: Not only are cat-eyes an absolute classic and always in style, they’re also one of the most universally flattering frame shapes. Look for shades that are in proportion to your face (they shouldn’t be oversized); and to avoid a dated look, steer clear of anything too costume-y, like rhinestones or exaggeratedly narrow shapes. To buy:For a similar product: $175; bloomingdales.com. These frames can be ultra-modern or have a 70s-throwback appeal. But buyer beware: Because of the low-dipping triangular lens shape, this silhouette can make round or square faces look a bit unbalanced. You need a face that’s a little on the long side, or a narrow chin that echoes the lines of the lenses, to really pull off this style. To buy: $55, perversesunglasses.com. Square and rectangular frames look great on faces that narrow toward the bottom. The width of the lenses and their angled shape can overemphasize stronger jaws, so these are best suited to those with softer lines. To buy: For a similar product: $310; nordstrom.com. The curves on round frames soften the angles on square- and heart-shaped faces, and oval shapes have the length to balance this style. Avoid the circle look, though, if you also have full cheeks, as the lenses will just accentuate that shape. To buy: $98, shopsonix.com.