Things You'll Need
Instructions
Ensure that both your Xbox 360 and your cable or DSL modem is powered off and all unplugged.
Connect the Ethernet cable to the Ethernet port in the back of the Xbox 360 game console to the Ethernet port on your modem.
Turn on the modem by plugging it in and powering it on, ensuring it is connected to your cable outlet. Wait for the modem to confirm that it is connected to the Internet (most cable modems have an "online" light that stops blinking and stays on when an Internet connection is set) and then turn on your Xbox 360 console. Make sure there is not a disc in the disc drive when you turn it on.
Select the Xbox Live selection from the menu on your Xbox 360 dashboard. At this point, you can either start a new Xbox Live account or log in to one that you already have established.