Bring your arms forward until they are above your head (fingertips pointing to the ceiling).
Lift your head, and together with your arms, roll your spine up one vertebra at a time, keeping your navel pulled into your spine.
Roll up completely until you are bending forward reaching toward your toes.
To return, pull your torso back so you are sitting with your shoulders over your hips. Then slowly roll down until you are lying flat on your back again with arms overhead.