How do I make a private repo public or a public repo private?

Changing the privacy of your repo is easy.

1. Be an admin of the repo
2. Visit repo->settings
3. If you want to make a repo private, check Settings-> Visibility [x] Make Repository Private
4. If you want to make a repo public, uncheck Settings-> Visibility [ ]Make Repository Private
5. Click "Update Settings"
6. You can verify if a repo is private by looking to the right of the top repo name (see gif below)