HOW: Place a slider under the leg you do NOT want to work. The working leg is the leg that does not move. Slowly lower your body and slide the slider out behind and out to the side of you into a curtsey lunge position. Then return back to the starting position by 'pulling' yourself back.
FEEL: You should feel all the muscles, especially your glute muscles, in your stationary leg working to perform the exercise and maintain your balance.
COMPENSATION: Do not put too much weight through the slider! Pretend there is an eggshell under your foot.