Yesterday, I was planning how to smooth out an uneven edge with the best appearance, and least waste and effort. I did a quick sketch of how I first thought of doing it. That suggested an improvement, which gave less waste but much more work. Then I saw a far better solution. A few hours later, while congratulating myself, I got another idea, and the sketch showed it was the "obvious" solution. - Easy, economical, and attractive, and also solved a minor problem all the other solutions had over the width of the saw cut.
I guess it is an iterative process. I try to draw what I'm thinking of, and then get better ideas from the things that show up on the paper.