First pin the cable height to the lowest position then pin a suitable lifting weight. Sit at the front end of a flat bench with your feet on the floor and positioned in the centre of the cable rack.
Lean over one at a time to grab the cable handles then rock back so that you are lying flat on the bench with arms outstretched taking the weight of the cables. Your arms and the cable line should be perpendicular to the cable weight rack and the palms are facing each other. This is your starting position.
With a slight bend at the elbow, squeeze your chest to bring your outstretched arms together above your body over 1-2 seconds as you exhale. Pause at the top of the movement for a brief second.
Now reverse the movement inhaling as you do, to bring your arms back to your side until your palms face the ceiling and the chest is at full expansion. You should feel the chest muscle being stretched and opened right up.