Before you begin this exercise you should first be able to feel your energy on a physical level and have full control over it.
The exercise - Begin by standing up. Breath with your throat slightly constricted and breath in energy from the air and channel it to your stomach area. Then at the same time channel the energy from the base of your spine also into your stomach area. After you have all that energy in your stomach area flex your stomach muscles to raise the density and force the energy to expand outward. Each day you do you should have stronger energy.