Sit facing the lat pulldown machine with your knees locked under the roller pads. Grip the pulldown bar with your hands slightly wider than shoulder-width apart and palms facing forward. Lean back slightly from the waist keeping your back straight. (Not sure how much weight to use?)
Inhale and then exhale as you pull the bar down in front of your face until it reaches your upper chest.
Inhale as you return to the starting position.” SOURCE