Begin with your knees on the floor and your upper body resting on the fitball
Place your hands about shoulder width apart on the fitball, with your fingers spread out wide to give you extra grip
Slowly straighten your arms as you push your body off the fitball. Keep your body straight
Now slowly lower your body back towards the ball without letting your chest touch the ball
Repeat steps 3 and 4 until it you can no longer maintain your technique
Tips
If you are performing this exercise on a slippery surface, try putting a towel under your knees
If this exercise is a real struggle try placing the ball against a wall for extra stability, once you are a little more comfortable with it move away from the wall