Sit in your wheelchair with your feet resting on the footrests beside a solid object such as a table.
Ensure your brakes are applied.
Rest your elbow on the end of the table in front of you.
When ready, lower your hand and forearm to the space at the end of the table and apply downward resistance with your other hand to feel the stretch in your shoulder.
Hold this position for the duration as instructed by your therapist.