If I ever get around to writing a how-to cartooning book (something I have actually considered), one technique I’m going to champion is learning how to pencil and ink with a real, live–and often moving–cat on one’s drafting table.  My thinking is that this is kind of like those “heavy hands” things that some folks go running with: if you can pencil and ink with a cat moving around on your work surface, then you should be really good at it when there’s not a cat moving around on your work surface, right?  I recently drew and inked–and inked with a brush pen, in fact–a drawing while I was in a moving bus going up a mountain in a rain storm.  I credit this cat-style cartooning technique.