Straighten your body, so that your heels are hardly resting on the wall.
Push on your fingertips (think of grabbing the ground) to make your heels come off the wall and try to balance for a few seconds before leaning on the wall again.
Form tips
Aim to open your shoulder to 180 degrees (full Shoulder flexion backward ).
Keep a posterior Pelvic tilt and avoid arching your back.