The top hand is the "power hand" in the swing. It starts out on top, trails the bat and lower hand as the hands go to the ball and eventually becomes the lower hand.

Take a light bat and hold it with the top hand only in the proper hitting position. Place your other hand across your chest. Take your bat directly down to the ball on the T without rolling over your wrist. Keeping your fingers visible, flip your wrist slightly to bring the barrel of the bat down at the point of impact.

The bottom hand is sometime referred to as the guide hand or action hand. It leads the way and provides the action in your swing.

Take a light bat and hold it with your bottom hand only in the proper hitting position. Take the knob of the bat directly to the ball on the T, you should be looking at your thumb knuckle. To complete the motion simply roll the wrist and forearm and continue the follow through up and over the shoulder.