Sit in a Smith Machine with your buttocks at the top angle of the decline bench (angled at 15-30 degrees) and position your feet under the ankle rolls. Slowly lower your torso backwards onto the bench.
Take a medium width grip on the bar, retract your shoulder blades and arch your back slightly. Unhook the bar so that you are at full arm extension above your chest and settle yourself. This is the starting position.
To commence the movement, lower the bar over 1-2 seconds as you breathe in. The bar should just touch your upper sternum at the bottom of the movement but without bouncing off the chest.
Raise the bar over 1-2 seconds as you breathe out and return to the starting position.