PSP 1000 CFW Help

[DioWolf]

This is my first time adding custom firmware onto my PSP fat 1000. I have a pandora battery for it and a memory stick of 4GB. The firmware it is currently at is official firmware 6.31. It's module is 01g

I have searched and searched for several hours now on how to actually add custom firmware and how to downgrade but alas nothing has been of proper use or made sense.

So can someone here please provide me with a tutorial or tell me how to install CFW?

Any that is 5.50 is okay as the main reason to why I want CFW is so that I can play Kingdom Hearts Birth By Sleep Final Mix but with the English patch added to it. I can do that bit myself however.