1.) Lean back and prop your upper body up on your elbows (your back should remain lifted), palms facing down. Brace your abs in tight and lift your legs into a 90-degree angle (knees should be touching), toes pointed.
2.) Slowly lower your legs over to the right (knees should stay together). Keeping the 90-degree angle, lower your legs & then lift them up to the left. That is one rep. Perform 20 reps.