I have been drawing these since before I could spell them
Graphite on cartridge paper, most of it done at a desk with two pencils. Some sheets are studies where the proportion is the whole point, and some are one corner of a car drawn until the light on it reads right.
Form
The sheet is the drawing
Proportion studies, package drawings, and the odd interior section. Wheelbase and overhangs get set first, because the proportion is the decision and the surface is what follows from it.
The package drawing is where the interior stops being a shape and starts being decisions: how many seats and where, how far the display runs across the dash, and a note to myself asking whether the wheel sits inboard or outboard of it.
Interface
The screen in the cabin
Automotive HMI, listed here and written up in full on the work index.