Lie on your back and reach your arms rigidly to your side, off the floor. Lift your legs off the floor, and point them, so they are at about a 45-degree angle. Lift your head so your shoulders are off the floor as well.
When you're ready to begin, lift your upper torso off the floor and bend your knees. You can lean back to make this move harder or come up more to make it easier. This is similar to a modified Boat pose in yoga.