Set the bar around shoulder height. Stand under the bar with your feet slightly in front of you. You're aiming to keep your hips and spine in the same alignment as the smith machine as you descend.
Grasp the bar with a wide grip and position the center of the bar on top of the muscles on your back. The bar should not sit on your neck.
Keeping your back straight and your eyes facing forwards, take the weight off the rack.
With your back straight and your eyes facing forward, slowly squat down to your full range of motion while not breaking form.
Push up through your heel and raise the bar back to the starting position.