The main line of development is the master branch in the primary repository. The master branch always contains the latest, potentially unstable work.
When a version release is impending, a feature freeze happens, and a separate openmw-x (where x is the version number) branch is created. Only bugfixes and well-tested or non-disruptive changes are accepted into that branch.
Developers who want to work on a new feature or a bug-fix are requested to created a new topic branch based either on the master or the openmw-x branch. Usually the master branch should be chosen over the openmw-x branch. But when in doubt, please ask on the development forum.
The topic branch shall be given a short, descriptive, all-lowercase name.
Additional topic branches should branch off from the master / openmw-x branch, unless they depend on another topic branch.
Once a topic branch is ready, the developer should issue a pull request on github into the target branch of the primary repository. If you are unsure if the branch is ready, ask on the forum first.