I took progress photos of the second half of my Pacific Crest Trail painting, and turned them into a GIF, so you can watch the sky coming together:
After filling in the background colors with a large brush, I started putting in the stars. I had a breakthrough in my starry sky paintings when I stopped using mostly black, and used a mix of blues instead for the background colors. This painting has very little black. The main sky color is Anthraquinone Blue, a strong transparent blue, with some Phthalo Blue and Titanium White.
Another trick I’ve learned: use the handle end of the brush to make the stars. They come out rounder, and you can adjust the pressure to make bigger or smaller dots.
I like to vary the colors of the stars to add depth as well. For some, I used a mix of Titanium White and Phthalo Blue, then added white dots over top after the first dots had dried. For others, I used a bit of Titan Buff instead of white, to make the stars yellower.
After putting in most of the stars and letting them dry, I experimented with the colors in the sky by adding in a bit of Quinacridone Magenta and transparent Zinc White here and there over top of the stars.
I also added a bit of the magenta to the snow on the mountaintops below to tie it together. Here’s the finished painting: