Stand with your feet slightly wider than hips-width distance apart in front of a sturdy box that's six to 24 (or more!) inches tall.
Bend your knees and swing your arms back.
Jump onto the top of the box with both feet, swinging the arms forward to give you a little momentum.
Turn and step one foot at a time down to the floor on the other side of the box. Now you're facing the opposite direction that you started. To make this easier, just step down to the starting position instead of stepping over to the other side of the box.