I conduct an occasional workshop for colleagues on the use of Git and GitHub. The target audience is scientists who may be not necessarily be using these tools in a software development context.
We generally start with a conceptual overview of version control concepts, and conclude by making collaborative edits to a repo containing a single file. I ask participants to clone the repo, add their name and bio to the file, and open a pull request.
I encourage participants who are not already proficient on the command line to use the GitHub Desktop clients instead of the git CLI. I think any choice is fine and support both, but if typing out instructions to the computer is a new concept (which it is for many!), it's better not to be distracted by this when trying to learn the core version-control ideas.
Here are slides that I most recently used.
Some form of this workshop was given on three occasions: