To get started paint a lovely base of blue. After it completely dries the fun starts. Take a tad of raw sienna mixed with a bit of dioxazine purple which makes some brilliant sunset shadows in the clouds. Then add some white to the clouds. Last add a bit of yellow oxide and highlight some of the clouds to simulate the sun's bright beams on them. 2 hours later ~ voila! A sky.
This was great to paint especially since we were all overcast yesterday. Made my day shine! hehe
Everyone have a great day!