You simply screw it into any light fixture, screw in a bulb, turn the power on, and then send it a code from any X10 Controller. You send the same code three times. When the Socket Rocket receives the same code for the third time it turns on the light to let you know that it has "learned" the code. It then remembers this code indefinitely, even if the power fails. To "teach" the Socket Rocket a new code, you just remove the power, reapply it, and then send a new code three times.