Place the 2-inch by 4-inch piece of wood horizontally across the sawhorse.
Hold the 2-inch by 4-inch piece of wood steady with one hand.
Pick up the handsaw with your other hand and cut the 2-inch by 4-inch wood in half.
Position yourself with the strobe light and 2-inch by 4-inch halves to the side of the stage. You will remain unseen, but the strobe light will be visible to the audience.
Plug the strobe light into an outlet.
Switch the strobe light on when the lightning is queued. Simultaneously slap the 2-inch by 4-inch halves together a single time to simulate a thunderclap.
Switch the strobe light off.