You could carry around a gigantic whiteboard all the time and look like some crazy professor, or you could invest in a Wipebook. Wipebooks are basically notebooks that swap out the standard paper pages for whiteboard-esque sheets. What this results in is a smooth writing experience (think pen compared to pencil) that is also erasable (think pencil compared to pen). Your notes and doodles won’t get erased from simply sitting in the notebook and you’ll be able to work in a range of colors. As long as you’re willing to erase your notes every once in a while, you may never have to buy more than one.