Pull the pin from the weight stack, so you are lifting just one plate.
Place your feet on the step and slide your shoulders under the pads.
Slowly lower your heels to the floor (with one-third of each foot on the step).
Lower your heels as much as you can (with your legs completely straight). If the moving part of the weight stack touches the part that stays in place, you need to move the shoulder pads down to allow for a full movement range.
Step off the machine and select a weight you can use for eight to twelve reps.
Slide your shoulders under the pads and place your feet on the step.
Stabilize your position by grasping the top or side of the machine.
Slide forward or back so that just the top third of your foot is on the step.
Adjust your foot position; your feet should be 1 to 6 inches apart.
Keep your feet pointed straight ahead (don't point your toes in or out).
Center your shoulders under the pads and slowly straighten your legs. Rise up on your toes as high as you can (without looking down at your feet).
Pause for one second when up on your toes, then slowly lower the weight.
Lower your heels as much as you can without sliding back on the step.
Repeat until you reach failure (you can't perform any more reps with strict form).
Other Key Points and Reminders
Never bounce or jerk the weight up; make sure every rep is controlled.
If you have (or have had) a knee problem, your knees should stay slightly bent.
Always stay centered under the pads and try not to arch your back.
Never wear old or worn footwear when you are using this type of machine. Your shoes should have a tread pattern that will give your feet some grip.