Get the most out of your Pilates ball, by picking up a few of these Pilates exercises outlined in this tutorial by Pilates instructor Ann Arnoult. For stability, do the plank exercise with your feet on the ball and your hands on the floor which forces you to use your abdominal muscles to maintain that position. Another exercise is to sit on the ball. You will need to sit with your back straight and tall on the ball. Bring your hands behind your back. Inhale and then exhale, but while exhaling roll down on the ball pressing your back against the ball. Then roll back up. A third exercise is called superman where your press your pelvic bone against the ball as you inhale. Then, exhale. Inhale again as you reach your arms straight out ahead of you.