Once your hands are positioned, it is time to open the pot to the desired depth as you throw on the potter's wheel.
Gently push downward with your left hand on the backs of your right-hand fingers, keeping your right-hand fingers straight. Because your fingers were across the center point, the clay will automatically move away from the pressure so that the opening is centered as well.
Be sure to keep the clay well lubricated during opening. Continue the gentle downward pressure on your right-hand fingers until you think there is about a half inch of clay between the bottom of the opening and the bat's surface.
Stop the wheel. Use your potter's needle to check the floor's depth. It should be between a half and a quarter inch, unless you are planning to trim out a foot when the pot is leather hard.