Place a decline bench between two low cable pulleys.
Grasp the stirrups (handles) of each pulley, lie supine (on your back) on the decline bench, and hook your feet under the pads.
Position the stirrups out to each side.
Flex your elbows slightly, and internally rotate your shoulders so that your elbows point out to the sides.
Execution
Keeping your elbows slightly flexed, exhale as you press the stirrups upward and inward in a hugging motion until they nearly touch over your chest.
Hold for a count of two and squeeze your chest.
Inhale as you reverse the motion and return the stirrups towards the starting position until you feel a mild stretch in your chest or shoulders.
Repeat.
Comments and tips
Keep your elbows slightly flexed.
Keep the movement slow and under control.
Internally rotating your shoulders allows for better isolation of your pectoralis major because it brings the origin and insertion of the muscle into better alignment.