I agree that coming up with pictures is challenging. I’ve been working on this for several months now, and find that more images get into my repertoire with time. I read the term “visual vocabulary” somewhere and am trying to build one. For instance I need to be able to draw a computer, books, pens, etc. Also stick figures. And because I work with students who are themselves teachers most likely in Texas, I decided to learn to draw the State of Texas. That is hard! hahahaha I am getting better. You are right that it is fun.