Tom Clifford, a certified personal trainer with Gold's Gym, teaches us how to do squats. In this video, he uses a 20 pound barbell, which is not a lot of weight. You put it behind your neck, and rest it on your "traps," or the top of your shoulders. Place your feet shoulder width apart, and keep your back straight and flexed. Go down as if you are going to sit in a chair. Your knees should be over your heels, not over your toes. Go all the way down into a sitting position, then back up. That's one rep. Do about 3 sets, about 15-20 reps each for muscular endurance, a bit less if you are training for muscular strength.