Begin with your knees on the floor and your upper body resting on the fitball, hands joined together and rest your chin on them keep your elbows by your side
Now lift your knees off the floor so your body is in a straight line from heels to shoulders
Now lift your chest off the ball and begin SLOWLY rolling the ball forward with your elbows as far as you think you can manage
Again using your elbows, slowly roll the ball back towards your body
Repeat steps 3 and 4 until you can no longer maintain correct technique
Tips
For this exercise to be effective, ensure you contract your stomach muscles throughout the duration of the exercise
With the exception of your arms, try to keep your body as still as possible