Plate a suitable weight and take position sitting in the leg press machine with your back pressed against the pad and your feet placed on the foot platform at shoulder-width. For the most effective movement you need the greatest range of motion - set your feet so the toes are pointing upward and the back half of your feet and heels hang off the plate. You should maintain a slight bend at the knee and your head is up. Now, drop the heels down as low as possible without your toes slipping off the plate. This is your starting position.
Commence the upward phase by exhaling and contracting the calves so that you come up onto your toes. Take your ankles to the maximum height you can and squeeze and hold at the top part of the movement.
At this point, commence the descent by inhaling and slowly lowering the heels back to the starting position.