This is one of the hardest part for me, to get the proportions right.
I never had the idea to use a waterproof pen to block the darkest areas, so it was a nice thing to try. Of course, I evaluated several art supplies using Kendyll's example and did swatches to test them on a separated piece of paper.
I was going to do the left one with liquid watercolor, but once I started the right one with the copic markers I decided to do both first layers with them.
I'm still working on them.
I decided to do just one bird and here is the final piece: