You can download skins or make them yourself:
Dl them @ www.xbox-scene.com
Or make them:
Look on your xbox HD in map useually C:/skin/ their maps there that have the names of the skins u can use in Evox.
Choose one u dont like and delete the pics in it and replace them with 2 pics you do like.
Next thing you should do is change the .ini file thats in the same folder as the pictures.
you should change it like this:
Half way of the ini file stands:
Main = "\skin\Armageddon\<picture name>.jpg"
Launch = "\skin\Armageddon\<picture name>.jpg"
where <picture name> should be the filename of the picture you put in the same folder.
Change it (without the < > characters) into the filename from the pictures.
Save the ini file and reboot your xbox than choose the skin you just changed
If you want the letters of the skin in another colour you should change this values:
MenuColor1 = 0x000000
0x000000 is black
0xC99E00 is white