Position
Place your hands onto the bar so that when your upper arms are parallel to the floor, they form an approximate 90-degree angle with your forearms. Sit with your knees under the pad, and lean back somewhere between 15 to 45 degrees. Hold the bar with your arms slightly bent and your elbows pointed out. Pull your shoulder blades down and together, and create a natural arch in your lower back.

Technique
Contract your lats, bend your elbows, and begin to pull your arms out and down until your upper arms are about parallel to the floor. Keep your shoulder blades depressed and squeezed together, your spine stabilized, and a natural arch in your lower back. Hold, continue to contract your lats, and relax your hands and arms as much as possible. Raise your arms back up slowly to their original starting position keeping tension in your lats. Repeat.