[kaylarose]

ASAP.

If you are worried about overloading them with technical info, I find it really easy to introduce people to version control with a "Contributing to a Book" metaphor. Where you have multiple authors and editors all working on a book at the same time, and it's important to know who changed what, and when.

Then, have them start using Git/SVN/Whatever to control any papers, notes, or assignments. I've taught multiple non-developer types how to use version control using this method.