Take an overhand grip on a barbell, just outside of shoulder-width. You may lift the barbell from the ground however for heavier lifts, setting up in the squat rack can be beneficial.
Your feet should be planted firmly, knees bent slightly. Your core is tight and your torso is angled forward from the waist but making sure not to arch your back over. Keeping your head up, take the weight of the barbell and let your arms hang down perpendicular to the floor. This is the starting position.
Commence the movement by pulling the bar up and back, squeezing your shoulder blades together. The elbows are not flared - keep them close to your body while you exhale through the movement. Do not use momentum to pull the bar. The torso should remain stationary.
When the bar just touches your abdomen, squeeze for a second and then reverse the movement by extending the arms to the starting position, inhaling as you do.