My training started way back with a thing called a pencil. Remember those things? A lot of "modern" designers don't use them anymore. I do. Although the results aren't anything you'd want to hang on your wall, except to say "Ya, believe it or not, that's how that gorgeous piece of furniture started...". My chicken scratches always capture (in my mind) a root concept and within 5 minutes a 3D concept is evolving upstairs. From there I either start building an 1/8th scale model or I pull up SketchUp and start a digital model that I can spin around and email to my client.