In order to pull push changes to/from a repository follow these steps:
mkdir your/repository/
cd your/repository/
git clone - Creates a local copy of the remote repo.
git clone https://github.com/YourUser/YourRepo.git
git branch - Tells you what branch you are at
git pull - Sync the remote repo locally
git checkout -b unstable origin/unstable - Creates branch "unstable" locally with the contents from the remote unstable repo
git checkout master
git checkout unstable - Syncs the remote unstable repo locally
Edit the files you need and then…
git status - Will tell you the next steps to perform.
git add debian/rules - Add the file debian/rules to the list of files you will be working with
git commit -m "File modified to add xxx functionality" - Always commit with a comment to be able to quickly distinguish changes.
git push - Push your changes to the remote repository.