We assume that you have already finished with the basic tutorial before coming here. The additional information will give you some information about advanced Git techniques.
This document provides information about how to delete a branch from your repository.
Only do these steps after your pull request get's merged.
This document provides information about how to keep your forked repository up-to-date with the base repository. This is important, as hopefully you and many others will contribute to the project.
Follow these steps if your fork doesn't have any changes in parent repository.