Position
Lie prone on a bench with your knee joints aligned with the axis of the machine and the pad adjusted just above your heels. Hold securely onto the handles below the bench. Turn your head to one side, and firmly press your chest and pelvis against the pad. Begin with your knees slightly flexed and the weight just off of the stack.

Technique
Contract your hamstrings, and begin pulling your lower legs up slowly, keeping your pelvis pressed firmly down and lifting your knees slightly off the pad. Continue to press your pelvis down and pull your lower legs up until they form an approximate 90-degree angle with your upper legs. Hold, continue to contract your hamstrings, relax your feet, and stabilize with your trunk muscles. Slowly lower your legs down to the original starting position. Repeat.