Things You'll Need
Instructions
Remove everything attached to the Xbox 360 console except for your 20 GB hard drive.
Hold down the guide button on a controller until the lights flash. This powers on a controller and the console.
Attach the transfer cable to the new, larger hard drive. Insert the other end into the back of the Xbox 360.
Insert the transfer disc into the Xbox 360.
Follow the instructions as they appear on screen. Allow time for the process to occur.