Git Workshop: You're Doing it Wrong
This workshop by Rob O'Brien will walk you through some of the common pitfalls that you may come across whilst using Git and how to remedy them. What your commit message format should be, why you should be using 'git fetch' rather than 'git pull' and why rebasing is the way forward; as well as some more advanced concepts such as 'rebase --onto' and recovering lost work using 'git reflog'.
Also provided are some useful resources for learning more about Git or improving your workflow.