As part of my everyday egghead work, I make a lot of notes. Sketchnotes in particular.
Everytime we have a new course in production, I'll watch all the video lessons and sketch out the major points.
These help me give ideas for illustrations and diagrams we can build on top of the lessons.
Here's a small preview of it:
A giant, printable version will be posted on the Test Production Ready Apps with Cypress course when it's released later this month.