I’ve started shying away from graphical Git clients like GitHub Desktop recently. While they’re great for beginners and make visualizing the repository history easy, I wouldn’t want to be dependent on them and be lost when working on a machine that doesn’t have them installed or a remote server via SSH.
Of course, this flowchart doesn’t cover everything, and, unlike the guy whose phone number is in git.txt, it doesn’t really talk about branches. You’ll still be lost if you run into merge conflicts, for example. It does, however, cover a few common issues you might run into, like adding a file to your last commit or fixing a commit message (assuming you haven’t pushed/synced). To really master Git, check out the book here: https://git-scm.com/documentation. Also, remember to write better commit messages than these!