Start with a loaded barbell; 75 pounds is a great starting point. Beginners should start with just the barbell and gradually add weight as they become familiar with the movement.
Position your hands about shoulder-width apart on the barbell, and lightly grip the bar with an overhand grip.
Step in front of the rack, and rest the bar on your trapezius muscles (the muscle closest to your neck/upper back).
With your feet about hip-distance apart, lift the barbell off the rack. Take one to two steps backwards.
Shift your weight back into your heels. Brace your abs as you begin to lower into a squat, keeping your head and spine in a neutral position. Your knees should be as close to 90 degrees as possible. Hold for one second.
With your core still braced, drive through your heels to stand back up. Be sure to squeeze your glutes at the top of your squat. That's one rep.