git and branches newie questions

I need some suggestions for the best way to setup my repositories.

I have a linux repository cloned right from Linus.
I want to create 2 additional branches in this repository:
   internal_current and internal_testing

I want to use internal_current to make modifications to the main Linux
branch for an internal project.

I want other users to clone/pull/push changes to the internal_current branch.

I want to use internal_testing as a branch to merge and test the
latest Linux branch with changes made to internal_current. Once this
testing is complete, merge the changes into internal_current.

That is the best way to do this. I am open to use cogito. I have
messed up this merging process just about each time, and I want to get
a stable process before I open this up to other users.

Also, I can't figure out permissions. I have setup the allow_users
hook in .git/hooks/update. My repository is "owned" by gate_keeper. My
user login is dreiland. I push changes back to the gate_keeper
repository and stuff under .git gets owned by me. Now, I log as a
gate_keeper to get a Linus update or perform the internal_testing
merges and things fail because it is owned by dreiland.