While I have a north star idea, it don't usually mean I know all the pieces that make an effective image. Especially the part on how to generate each detail on screen. So I do different attempts and find out what to add or change.
Most of the time, I already have like a rough idea in my head. I'm quick to put them on paper to establish an overall vision.
Inspired by the hidden city of Numenor when I was watching Rings of Power. It made me curious how to make an iconic key environment piece.