Set-up: Find an immovable object that is positioned roughly arms length from the ground. A barbell locked in place, a desk or a chair may all suffice - simply make sure it is immovable and unbreakable, to bear your weight without incident. Now place a sturdy box or separate elevation a body length away. Lie on the ground with back flat on the floor and your feet on the elevation. Grasp the bar or object with both hands, such that a line forms between the shoulders, the elbows and the apparatus.
Lift: Pull yourself up - without sagging the hips or rounding the lower back - until your chest touches the apparatus. Squeeze the shoulder blades together at the top of the movement.