Start on your hands and knees with a smooth surface laid out in front of you. Have something heavy behind you that you can anchor one end of the band to and place the other band around the handle of the ab wheel. You may like to have your knees on a foam mat for comfort.
Holding onto the ab wheel with both hands, make sure your core is on and your spine is in neutral. Slowly roll your hands away from you in a smooth and controlled manner, allow your shoulders and your hips to move together without rounding through your lower back. Extend the wheel away from your body as far as you can control and maintain a neutral spine through the movement. Don't let your back extend as you roll out as you roll forward on the wheel. Once you have rolled out as far as you can, bring the wheel back in towards your hips and return to your starting position.

The heavier the band or adding on extra bands will make this easier.
Progress by decreasing the amount of resistance the band provides / removing a band.