Instructions
Turn on the Xbox 360.
Press one of the wireless headset's "Power" buttons.
Push the sync button, donning three wavy lines, on the front of the console near the "Power" button.
Hold the headset's sync button, donning three wavy lines, for one second or until the lights flash on the headset's dongle. The quadrants on the Xbox 360 console flash, indicating successful sync. The top-left quadrant indicates the headset is connected to the first controller. The top-right quadrant indicates it is connected to the second controller and so on. Repeat Steps one through four to connect the second headset to the second controller.