I recommend my students the following Git Cheat Sheet:
You don’t need to know the git commands and parameters by heart on the first day, it gonna take you some time to master it. Check out the Git Cheat Sheet as you go.
On the first day, you should understand how it works, the concept of local repository, head, server, commit, diff and pull and push.
Students, interns, and devs can look at the references as needed.