Wiring your home with Cat 5 Ethernet cable is a great way to provide everyone in your house with a wired Ethernet connection without the hassle of having visible wires everywhere. Once you run the wires, you terminate them at a wall jack. Someone wanting you use your home network then plugs another Ethernet cable into the wall jack and connects it to their computer. In order to use a wall jack, you must know how to properly wire the Cat 5 cable to the back of the jack.
Strip about 2.5 cm (1 inch) off of the end of cable jacket on the Cat 5 cable coming out of the wall. Untwist the wires. Fan out the various wires so you can work with each one individually. For Cat 5 cable there are eight wires total. Don't untwist more than about 1.2 cm (1/2 inch) of the wires.
Separate the Cat 5 jack from the wall plate, if they are not already. Simply slide the jack out of the wall plate socket. Remove the plastic header on the top of the Cat 5 jack. Some headers pop off completely, while others are hinged and simply swing back toward the front of the jack.
Slide each wire into the corresponding punch-down slot on the back of the Cat 5 jack. The jack's punch-down slots will be colour-coded to match the Cat 5 cable's wires. For example, the blue wire goes into the blue punch-down slot on the jack, while the green and white wire goes into the green and white slots. Make sure to slide the wires into the correct slot or your jack won't work.
Press the plastic header down on the jack to lock the wires into place.
Slide the jack, now connected to the Cat 5 cable, back into the wall plate. Hook the bottom edge of the jack on the bottom edge of the socket on the plate. Rotate the jack up to lock the top retaining tab in place.
Attach the wall plate to the wall with the screws that came with your jack.
Be careful not to plug the wires into the wrong slots on the jack. Cat 5 cable needs to be wired a specific way in order for the jack to work.