Lie on your back with your knees bent and your feet flat on the floor.
Place a pillow or towel under your head and look up towards the ceiling.
Visualise a pivot point going through your ears.
Gently nod your chin as though rotating around that pivot point without tensing your side neck muscles.
Start to lift your head off the pillow in the same movement while you continue to breath, expanding your lower ribs.
Hold this position, and gradually build up the time of the hold as advised.
Try to contract your lower stomach and pelvic floor muscles at the same time.