The best way to work on your abs
This exercise is best to strengthen your abdominal muscles with some basic movements, and include a ball that helps with the increase of stability.
The first step is to slowly roll down onto the ball, and to let your spine follow curve of the ball until you place your neck on a comfortable position on the back of the ball. Now you will put your hands at the sides of your head and place your feet hip-distance apart.
The second step is to draw your abdominal muscles. Then you can exhale and curl your entire spine up the ball starting from the neck up. You will flex at your torso until the space between the pelvis and the bottom of your ribs stops shortening.