START AT THE BEGINNING!
GM Designers Andy Hanzel, Tom Peters, Ed Welburn, Robert Menking, William Quan, Silvia Ramos, Jon Albert, and Pres Brunning demonstrate their sketch techniques. From the ’80s. From an age before computers ruled the earth.
The quality isn’t what it could be (it looks like a copy of a copy), but the content more than makes up for it.
Thanks to Don Leblanc.