If you're using Homebrew, just run `brew install hub` and you should be all set with auto-completion.
> If you want to set up Git to automatically have Bash shell completion for all users, copy the `hub.bash_completion` script to the `/opt/local/etc/bash_completion.d` directory on Mac systems or to the `/etc/bash_completion.d/` directory on Linux systems. ([Source](https://git-scm.com/book/en/v1/Git-Basics-Tips-and-Tricks#Auto-Completion))
## bash
*[Link to git auto-completion bash file](https://github.com/git/git/blob/master/contrib/completion/git-completion.bash)
Open your `.bashrc` file if you're on Linux, or your `.bash_profile` if you're on OS X and add:
```sh
# Make sure you've aliased hub to git
eval"$(hub alias-s)"
# And make sure that the git auto-completion is being loaded