Start: Set the barbell on the floor, perpendicular to one end of a bench. Lie on the bench with your head at the end by the bar. Reach back and grab the bar with a full, overhand grip that's just a bi narrower than shoulder width. Lift the bar over your upper chest, with your elbows slightly bent. Set your feet on the floor or bench, whichever you prefer.
Finish: Lower the bar back behind your head until your arms are in line with your neck. Pause, then pull the bar back up over your chest. Keep your elbows bent at the same angle throughout the movement.