Take a position with your feet a little wider apart than shoulder width. Let your arms hang loosely alongside your body.
From the starting position dynamically spread your legs and simultaneously stretch your arms above your head and then pull your legs into the starting position and your arms to the side of your body. Breathe regularly and keep your body core firm.
Keep your body core firm and do not bend at the waist and keep your pelvis in a neutral position all the time.
Pay attention to your knees during the jump down onto the floor. Keep your knees parallel with your toes, not letting them point toward each other.
Exercise in front of a mirror to watch and improve your technique.