The LED light can attach to a variety of power sources, find the correct attachment and plug in your LED light to the power source. Use the gel pen to apply an even coat of whitening gel to the surface of your teeth, try to avoid clumps.  Place the LED light in your mouth and turn the LED light on.  Once the light turns off your whitening is complete.  Rinse your mouth and the LED mouthpiece.  Store your LED light in a dry place.