I allow my hand to regurgitate the contents of my brain with a pen set at a low opacity.
In a layer below the basic colors I roughly color in a backround. Also add some details on one of the birds with a small brush. Use a smudge tool for the highlights and shading to make it smoother.
More detail in everything. Used a tiny brush for the feather detail.
Even more details. There.
The only reference I had was a small photograph of a toucan.
I was pretty proud of this when I made it a year ago. Now there are a lot of things I would change, but it's still one of my favorite paintings that I've done.