A yoga mat is pretty much a must for yoga practice — or is it? After all, you should be able to Down Dog on just about any surface.
If you don't have a yoga mat handy, or simply want to buck tradition, you do have a few options. A mat is usually best, but not having one doesn't mean you can't practice. The type of yoga you're planning to perform will dictate the alternative mat you choose.
The alternative you choose also depends on your tolerance for less resistance, slipping and pain. No option will support you quite like the modern-day yoga mat.
Specially made yoga towels are designed to lay over a yoga mat, but there's no reason you can't use them alone. Their made of a wicking material that absorbs sweat and water, so they stay sticky even when you're dripping in a hot class. Technically designed to be used with a yoga mat, their grippy bottoms will stick to a wood floor. You'll miss the softness and cushiness of a yoga mat, but still get something that prevents you from sliding in class. Don't confuse them with a basic bath towel, which will just get sloppy when soaked and slip around on the floor.
Gloves and Socks
Several companies make gloves and socks with grips to use when you bring your yoga on the go. The grips are similar to yoga mats but only exist at those crucial points of contact, the palms of your hands and the soles of your feet.
Pack them easily in a travel bag or backpack for an impromptu yoga class where you'll be mostly standing or balancing on your hands. These accessories won't support your knees, buttocks or back in seated, kneeling or reclined postures.
When at home, a carpeted or rug can support your yoga practice. Use a low pile if you'll be doing a lot of standing postures. Be aware, though, that you may have a tendency to still slide. The thickness of the pad under the carpet also matters; a thicker, cushier pad means your standing surface feels nice, but isn't very supportive when you lift one leg up in Tree pose.
A long-pile, shaggy carpet isn't the best option for a flowing class or Hatha class with lots of standing or balancing poses, but could be comfortable for a Restorative or Yin practice in which you're spending most of the time on the floor. You're also not likely to sweat in one of these quieter practices, so you don't have to worry about your carpet acquiring an odor over time.
One of the greatest yogi masters of all time, B.K.S. Iyengar, defined yoga for much of the 20th century. He discouraged, and even forbade, practitioners from using anything but their bodies and his accessories (including blocks and the yoga wall) during practice. A wood floor was all you needed to get your yoga on.
A wood floor does provide a relatively stable surface for standing postures and arm balances, such as Crow, but can be uncomfortable for kneeling poses such as Camel, Headstands and Shoulder Stands.