From a standing position, bend the knees, bring the arms back and lean the body slightly forward.
In one smooth motion, swing the arms forward and up, and jump as high as you comfortably and safely are able.
You do not need to perform the jumps quickly one after another. In fact, resting two to four seconds between jumps is beneficial to your joints and your skeleton.
Safety Tip: Landing with stiff knees can be very jarring to the joints so always remember to bend your knees upon landing. Jumps should not be performed if they cause you discomfort in any way, or if you have been advised not to jump by your physician.