Though bodywork is usually most effective with the friction of skin on skin, massage can be done while you are clothed. You should do whatever makes you most comfortable -- relaxation is of primary importance. If you opt to undress, keep in mind that you'll be partially covered at all times; the only exposed part of your body is the portion the massage therapist is working on. He or she will usually leave the room while you disrobe (be sure to remove all jewelry before a session begins -- it can get in the way of bodywork and interrupt your relaxation). Then, depending on what kind of work you're having done, the therapist will ask you to lie on the massage table on your front or back and cover yourself with a clean sheet or towel.