This section of the documentation is meant to explain the steps needed to perform by the maintainer of the Coppermine package each time a new package release is being made.
This page does not deal with the steps that end users need to make when a new package comes out.
This part of the documentation is not meant for end users of Coppermine, but only for developers. There is absolutely no support for this section, it comes as-is. If you're not a member of the Coppermine dev team, then the contents of this page are not meant for you.
In the first place you need to perform core actions on the Git repository level of Coppermine. For this purpose, you need to have write access to the Git repository, which is something you can not make up. A dev team member with project admin status needs to have granted you write access to the Git repository that is hosted at github.com. You need to have some experience in using your Git client before trying to accomplish the actions described here.