All styles
Paper
Cream dot-grid paper, a graphite pencil for the first guess and a fine pen for what is true. A hand sketches the idea in pencil, plots the real curve over it in ink, then crosses out the guess in red and carries the answer into the conclusion. Quiet and personal, with the scratch of pen and pencil on every stroke.
Paper
Thinking it through on a sketchbook page.
Fully customizable — a project theme can re-skin the palette and fonts of any role.