HOW: Begin in a split stance by placing one foot behind you. Lower yourself down and allow your back heel to raise off the ground. The motion on the back leg should largely be coming from the big toe. Push into the ground once you are as low as you can comfortably go and return to the starting position.
FEEL: You should feel all of the muscles in the leg working, you may also feel a stretch on the back foot.
COMPENSATION: Make sure to raise your heel off of the ground as you lower your body, don't let your heel stay on the ground.