First I sketched the art on the left ad-lib. Then I refined it when I drew the art on the right - on the same sheet of pc paper. That is, I used typists correction fluid (TCF) to cover over parts of the art on the left that I did not like and redrew on the dry TCF. In this way I refined the art. I saved time. Otherwise I would have had to start all over. By using TCF it is much easier to design art.