Sunglasses are the ultimate must-have accessory for summer. Not only do they protect your eyes and help minimize skin damage, but a great pair of shades simply makes you look cool in a way no other accessory can. With so many designs and materials to choose from, trying on different looks is half the fun. Retro styles are especially hot right now -- particularly the 1960s-inspired cat's eye design. For a more wearable, but still trendy, look, try aviators or sunglasses with circular lenses. If you prefer a classic pair of shades that will always be in fashion, you can't go wrong with slightly oversized sunglasses with black or tortoiseshell frames.