Side Plank with Hip Drop
Lie on left side with right hand on hip and left arm bent, legs stacked one on top of the other. Pull abs in and raise hips off floor so you're balancing on side of left foot and left arm. Slowly lower hips toward floor, then raise them again. Do one set on each side and then repeat.
One-Leg Press-Out
Stand with feet together and hands by chest. Shift weight onto left foot, bend right leg so foot is behind you, and raise leg out to side until it is almost hip level (or lower if this is too challenging). For balance, focus on a spot on the floor 8 to 10 feet in front of you. Once you've established balance, slowly straighten right leg, pressing heel out to side. Hold for a second, bend leg in, and press out again. Do one set on each side and then repeat.
One-Leg Squat and Slide
Stand with feet together, hands on hips. Shift weight onto right foot. Bend right knee and hips as if you were sitting back into a chair, keeping abs tight and weight off left leg the entire time. As you lower, allow left foot to slide out to side. Press into right heel and straighten rghtight leg, sliding left foot back in as you stand up. Do one set, then switch sides and repeat.