Hey, help with 580i, debranding

[BTMM]

This site as been referred to by other, and it looks like you guys know what your doing.

I could really use some help, can i have a guide to debrand a w580i black from at&t, and i'd really appreciate it if it was complete, and if it included a backup or failsafe(or the closest thing to it) method as well, and free of course ;)


thanks for your time and effort, and whatever advise or information you can give me.