Lay flat on your back with your feet flat on the ground

Now place your hands lightly on either side of your head keeping your elbows in

While pushing the small of your back down in the floor to better isolate your abdominal muscles, begin to roll your shoulders off the floor

Your shoulders should come up off the floor only about four inches, and your lower back should remain on the floor

At the top of the movement, contract your abdominals hard and keep the contraction for a second & begin to come down slowly again to the starting position.