Assumptions – You have already completed the first 2 steps
Put an XDSL (Damn Small Linux) LIVE CD in the DVD drive of your XBOX
Unplug the USB drive from the custom cable and plug a keyboard in. You can use a USB hub with this connection too. You will not have to use a mouse as the XBOX controller will work as one in XDSL
Reboot the XBOX
The LIVE XDSL Linux will boot up off of the CD. If this does not happen, there is more than likely a problem with the CD burn or type. Please refer to this list of compatable CD / DVD formats
If you are happy with the LIVE Linux OS, you can install it on your hard drive.
Using the “B” button on your XBOX controller