Lie on your back, and place your hands on the floor for stability as you bend one leg and lift the other leg off the ground. Your bent knee should be close enough to your body so you can just reach out and brush your ankle with your fingertips.
Press your heel into the floor and lift your pelvis up, keeping your abs tight and your torso in a flat line.
Slowly lower your body to the floor.
This counts as one rep. Complete two sets of 10 reps on each side.