You will need the following:
USB thumbdrive (at least 512 Meg is a good size, as this is a big install)the softmod install files
(updated file location as Megaupload is now dead: http://www.1337upload.net/files/SID.zip)Xplorer 360
(Program that allows you to inject files onto the Thumbdrive)
Decent computer running Windows XP or Windows 7 but will be testing under Wine in Xubuntu (I GUESS you could use Vista :S )
Device to connect Thumbdrive to XBox (i used my Controller
Game that can use an Exploit (I used the First Splinter Cell as any version will work. If you can't get that, the Original Mech Assault, or an Older version of 007:Agent Under Fire, as most of the newer ones will not work.)
Optional: 12 pack of your favorite frosty 'BEvERage'