How to Build a Rocker Board

Cut the plywood to a 4-foot-by-4-foot square using a circular saw.

Use the measuring tape to find the center of the plywood square. Mark the center of the board with a pencil.

Cut your 2-by-4 into four pieces, two of them 11 inches long and the other two 8 inches. These boards will be attached to the bottom of the plywood and contain the ball on which you will balance.

Lay the plywood flat on the ground and arrange the 2-by-4 pieces in a square around the center mark you made.

Trace the inside and outside of the 2-by-4 pieces onto the plywood. This will give you a guide for drilling pilot holes.

Remove the 2-by-4 boards and drill three holes on each side, inside the lines you just traced, for a total of 12 holes.

Screw in partially all 12 screws from the top side of the plywood. The screws should be just starting to come through the bottom side of the board.

Hold a corresponding piece of 2-by-4 against the back of the plywood and finish screwing the screws into the 2-by-4. Repeat this step with the other three pieces of 2-by-4.

Paint the top of the rocker board.

Sprinkle sand on top of the rocker board while the paint is still wet. The sand will act as a non-skid surface. Once the paint dries, your rocker board is complete.

Place the ball on the ground and set the rocker board on top of it so the ball sits inside the box on the bottom side of the board.