I've tried to go paperless many, many times. But keeping a notepad and a bunch of post its in my desk has been one of the most helpful tools I ever got.
I've even managed to hide all my pens, move notepads to desks and use some note-taking application instead. In the end, none of those managed to come close to the utility of having something to scribble notes fast, or to draw a very high concept of whatever I'm trying to explain.
Also, a desk full of post its, or even a monitor with a bunch of things around gives the impression that you're really busy working -- just be careful to not have too many post its, or it will look like you can't complete anything. It even beats Trello!