Instructions
Turn off your Xbox 360.
Plug the USB cord connected to your wired Xbox 360 controller into the front of your Xbox 360. The Xbox 360 USB ports are located at the bottom of the console under the on/off button.
Press and hold the main Xbox 360 button on your controller -- the big button in the middle with the X through it -- until it illuminates. Your wired controller and Xbox 360 will now turn on and you can use the wired controller as you would any other.