ooh it really depends, but sometimes I watch a movie and it gives me ideas (as it was came out of the Constantine movie!) From Eden came to me because I liked the imagery of when Minho has visions and wanting to see a different take on omegaverse than at the time I had read. Betelgeuse was literally a weird dream I had and I built it out of imagining the world and what minsung's relationship would be. sometimes I get bingo cards or fest prompts and it grows from there! (my 80s omegaverse came out of wanting to black out my sapphic bingo card with 1 fic.)
as much as I adore canon compliant minsung and other ships, I have moved towards enjoying interesting AUs to put them in and see how I would fit in who I like to think they are into those worlds. I know that's not for everyone, which is fair, but I just find it fun to work with! I've also admittedly have run out of cc ideas that I'd like to work on that aren't just smut-centric haha.