Here's some attempts I made at a diagrammatic intro for my next book. Things get complicated fast (esp Venn diagrams, it's one thing to think of 3 categories but then the overlaps, what are they supposed to be, plus the central one which is supposed to be some kind of big picture? too much pressure, egads)
So I also made a simpler one. Maybe the mess is interesting in and of itself? Could make for cool endpaper design: all failed diagram attempts mashed together, trying to explain themselves to no avail
I thought I'd be conscientious and look up the origin of the Venn diagram. Now I see that it's extremely math-y in origin and I wish I hadn't looked. Stuff to do with Logic. My brain feels less adequate now. Try worsening your day too by reading all about it HERE
Although feel free to take artistic license to make your own Venn diagram about a completely non-logical subject. Like what components go into the perfect breakfast experience, or something. Just plan on making several versions until it actually expresses what you meant to say.