Earlier this year, I started a 36x48" painting of a twisted tree against a swirly sky, and approached it by painting in the tree first, then the sky. I'm trying the same image on another large canvas, but approaching it in reverse. This time I've painted the background swirls first. Next I'll add the tree over it.
I'm very curious to see which method looks best. Hopefully this sky-first method because it's much easier and faster.