A: You don't need to dress head-to-toe in athletic costume—that's hokey and shouts "beginner." But who can argue with sports togs that combine function with fashion—like my cute, pleated tennis skirts with ball pockets?
You'll hear the serious yoginis talk about shopping at specialty sites such as Lululemon., Vickerey.com, prAna.com and Athleta.com, where they find eco-friendly organic-cotton gear, which is also growing in popularity. But you can also go for yoga pants and other workout clothes suitable for downward dog and other pretzel yoga poses from the likes of Victoria's Secret and Nike.
What's so special about yoga pants? They are snug through the hips and fit below the waist, designed for a full range of movement. The legs can be tight or flared, but the narrower ones won't flap around when you have your legs above your head. When it's cold, a cute look is to wear leg warmers—which you can take off before or after warming up—with capri pants.
Men tend to find shorts or capri-length yoga pants the most comfortable, and tight-fitting shorts allow guys to maintain modesty. Yoga tops are fitted, often with built-in bras, and sometimes with racerback or criss-cross straps that won't slip around, allowing maximum shoulder freedom. Wear a hoodie or pullover sweatshirt during savasana—the relaxation at the end of practice—to chase the chills while you cool down.
A wide stretch headband or bandanna will keep your hair out of the way. During your warm-up, you might want to wear short socks with rubber grips on the bottom to keep you from slipping. But yoga is basically a barefoot sport, where you use your toes, and your feet need to be in touch with the ground.