Now all you have to do is install the XBMC 360 skin. downladable from http://blackbolt.x-scene.com/?p=downloads
Install that into E:\dashboard\skins
Then go to system > appearance > look and feel > skin > MC360
So, you're done. Just go through the different options and choose the options you want. It is suggested that you set a static IP in network, so you don't have to find the IP each time you want to FTP, it just stays the same.
If you would like more tutorials, go to http://www.xbox-scene.com/xbox-tutorials.php
for their xbox tutorials. They are very good, and can help get you more ways to use your xbox than just video and music.
Any questions should just be in the form of a comment.