Sketching the composition for Rendez-vous started with simple means: paper, pencil, eraser, ruler and a dollar-store protractor. The next step (not so simple, but fun when you know how to do it): orthographic projection for the balloon stripes, and perspective grids for the architecture and the shadows.. Next, scan the sketch and paint on it digitally. This is a useful way to visualize the rich contrasts anticipated for a large drawing to be done entirely with charcoal.