If that is the case, do what what is necessary and return to this exercise later. However, be aware that sleep can also be your ego's way of avoiding having its true nature exposed. It is no coincidence that the term awakening is often used interchangeably with self discovery and enlightenment. In the early stages, try to find a balance between the sleep you genuinely require and the sleep that is merely avoidance of being here now . Sleep is not our goal here.
Awakening is our objective.
Gently and effortlessly become aware of your entire body and breathing. Take your time. As you encounter and become involved with each area, become aware of the blood flowing in that area. Be aware of the warmth that this flowing blood produces in that area. Be aware of a mild tingling sensation that occurs as you place your attention on that part of your body.