Things You'll Need
Instructions
Link Two Xboxes
Turn both Xbox systems off.
Hook each Xbox to its own television or monitor. System Link will not work in "split-screen" mode and requires each console to have a dedicated display.
Plug one end of the System Link cable into the Ethernet port on the back of one of the Xboxes.
Take the other end of the System Link cable and hook it up to the Ethernet port on the remaining Xbox console.
Turn both Xbox consoles on and navigate to your game's multiplayer menu. You should see a "System Link" option or instructions on how to play.
Link Three or Four Xboxes
Turn off all of the Xbox systems as well as your router. If everything is powered down during the connection process, the connection should be active upon turning everything back on.
Connect every Xbox system to its own television or monitor display. Similar to hooking up two systems, when hooking up three or four you will need a television or monitor for every Xbox.
Plug one end of the first Ethernet cable into the Ethernet port on one of the Xbox consoles, then plug the other end into your router. Repeat this step for the other Xboxes, with one Ethernet cable per Xbox running into the router.
Turn on the router and allow it to boot. This may take a few seconds.
Turn on all of your Xbox consoles and proceed to the multiplayer menu for your game.