I used a purple color Sharpie and a stack of white cover stock. I was lying on my stomach on the bed… a soft surface that forced a looser product. I think I drew about 30 cats total, and this was the only one I loved. Sometimes it takes awhile. I tried to keep my lines simple and expressive. If I got stuck, I would switch to my left (wrong) hand. Some of the good ones were with my left hand…. Here is one of the full pages of sketched cats: