You will require someone to assist you with the exercise.
Lie on your back on a bed.
The bed should be at waist height for your assistant if possible.
With help from your assistant, bend the knee up that is furthest from them so your foot is flat on the bed.
Reach your arm across your body towards the side you are rolling.
Your assistant will be standing on this side.
Your assistant will place one hand on your hip and one on your shoulder.
On the count of 3 they will assist you in rolling onto your side.
Return to the start position.
Join in with the movement as much as possible.