checkout this project, feel free to make branches, commits, whatever.
push them willy nilly.
here's some git documentation:

starts off with most common git operations and gets more and more in depth
http://book.git-scm.com/3_getting_a_git_repository.html

in depth guide to most aspects of git (i haven't read all of it)
http://progit.org/book/

this describes the motivation for different aspects of git in a really
accessible way
http://tom.preston-werner.com/2009/05/19/the-git-parable.html