I’ll add more to this post as I go along; this is stuff that just evolves out of doodles and accidental marks on paper. I find it’s interesting to build up layers of pen marks and watercolours/ copic markers and let the two inform each other. So if I see a shape forming in marker, I explore it with the ink pen; then I add shadow and colour or whatever with a brush or marker and then back to the pen to explore it further, and so keep switching back and forth between pen and markers/ water brush. None of these are ‘planned’; no pencil underdrawing or anything, just imagining and visually brainstorming.
But before I took up my Tombow pen and decided to make the watercolour marks into dragons, the sketch started off like this: