You'll want to start here bro, once you've DL'd the editor click on the "Help" button or where you see that icon book...in there everything is explained and broken down for you to follow as per its use and instructions also there is a link where you can ask Finn himself if you have further questions, keep in touch and good luck again read everything carefully to insure you're applying it correctly.
I'm not sure if you're aware of this but you'll need the use of an AR device to actually DL'd the rosters in order to use Finns editor with them and they are exclusive to the current Xbox system
for these particular rosters incase you didn't know.
http://web.tampabay.rr.com/flyingfinn/roster.htm
Holla Back ya'll
Rickster101 aka "Jack Bauer"