You may contribute to Byobu by branching the source from Launchpad (ideally), or by forking the project on Github (less ideally):

$ bzr branch lp:byobu

$ git clone git://github.com/dustinkirkland/byobu.git

You commit changes locally, and then propose a merge in Launchpad (ideally), or submit a pull request on Github (less ideally).

As for coding standards, please use tabs, rather than spaces.  Thanks!

:-Dustin
