Squats are one of the most important compound exercises and I absolutely love them. I recommend that they be added into any serious exercise program. If you want to perform either a back or front squat with a barbell, the body weight squat is a great introduction to the movement . This is a short tutorial on how to perform a proper body weight squat.
Head: Head and chin down. Neck should be in a relaxed and “neutral” position. Fix your eyes on a point on the floor about 4 or 5 feet in front of you.
Shoulders: Relaxed. Be sure to not hike them up to your ears
Back: Keep straight. Not rounded, not arched.
Arms: You can put them over your head, or swing them in front on you (as I do in the video)
Feet: Should be slightly wider than shoulder width, toes pointed slightly out (about 30 degrees).
Knees: Should stay in line with the feet and should not travel too far forward.
Hips: In the lowest depth of the squat the TOP of the hip should be parallel with the knee (see picture). Going this low actually protects the knees by transferring force to the hamstrings and glutes, from the knees.
Body weight squats are a great stand alone exercise and can also be used as an effective warmup stretch. I use body weight squats before every workout. Here’s a video of a set of body weight squats.