You don't. The DVD player needs to be hooked up to the TV or to a receiver that is hooked up to a TV. Both the dvd player and the cable box are "output devices" that need to go into the TV. Output device does not go into another output device. If you need more detail then just ask but be prepared to let us know what make and model of TV you have or at least what kind of inputs the TV has and what kind of outputs the DVD player has.