On the other hand, I make visual art: Usually drawing and painting, but sometimes I head into sculpture. Ideas don't always come when I can actually do them - and sometimes I have to source materials and things to do an idea. Sometimes the idea isn't complete and I need to add to it before beginning, and sometimes I start yet stop part of the way through.
It simply isn't linear enough to do as you say.
I'm not really sure why it is stressful this way, though. I nearly always have something to work on that have various difficulty levels and it isn't a big deal if I don't get one or two done - some never get done at all. Of course, it depends on how many ideas you actually have. Good time management is a plus sometimes, which seems to take care of some of the stress.
Currently I'm designing a large VR environment for a game. Without notes of what needs to go where and when, that would be going... less well.