To use with an ssh key, you need a `git@github` url. So if you have e.g.
```plaintext
https://github.com/johnallsup/javascript-games
```
you need to
```plaintext
git remote set-url origin git@github.com:johnallsup/javascript-games.git
```

Then add your `id_rsa.pub` (or other public key) to github via settings.