This video shows how to initialize a git repo in an Xcode project, upload to a new GitHub repo, then commit and push to that repo.
Also, kids, commit, push, and fetch frequently! And using branches is a good way to avoid most merge conflicts.
-- LINKS --
http://jasperreddin.com
Unreal Gravity: http://unrealgravity.jasperreddin.com
GitHub Desktop: https://desktop.github.com