Set a single hand attachment at chest height on a cable machine and grab onto it with both hands, palms facing eachother.
Take a few steps directly out to the side and stand with your feet spaced shoulder-width apart. You should be looking straight ahead with your knees slightly bent, chest puffed out and shoulders back.
Under complete control and without letting your torso sway forward or back, fully extend your arms out in front of you, pause briefly, and then return your hands back to the starting position.