The light will have a red and a black clamp that you'll attach to the positive and negative posts of the battery, and an inductive pickup clamp that you clip around your #1 spark plug wire (the right-front wire). The clamp is marked as to which way should face the plug, so make sure you have it on there right. Make sure all the wires are away from any moving parts, start the engine, and turn the light on. Point the flashing strobe light at the timing pointer just above the harmonic balance on the front of the engine (the main pulley on the lower front of the engine). The pointer is a little toward the left side of the engine, so that's where you want to shine the light. Read your timing setting on the markings on the side of the harmonic balance. They might be hard to see, so it helps to wipe some white paint into the markings with the engine off.