Take a pronated grip on a low bar (ideally the bar is lower than chest height) so that you can begin in a squat position.
Start in a passive hang, shoulders elevated towards your ears. Maintain straight arms throughout.
Grip the bar as if trying to bend it. Depress and retract your scapula - shoulders away from your ears, and pinch your shoulder blades together.
Contract at the top, lower with control. Repeat for reps.