Lay on an exercise ball with your lower back pressed against the ball

Your feet should be bent at the knee and pressed firmly against the floor

The arms should either be kept alongside the body or crossed on top of your chest

Lower your torso into a stretch position keeping the neck stationary at all times

This will be your starting position.

With the hips stationary, flex the waist by contracting the abdominals and curl the shoulders and trunk upward until you feel a nice contraction on your abdominals keeping the lower back always in contact with the ball

Hold the contraction for a second and then slowly go back to the starting position.