For awhile when I was driving around and would see an amazing sunset, I would actually get angry that I couldn't pull over on the freeway that second and paint it. It really kills the natural enjoyment of a sunset, let me tell you!
Well, a couple months ago I was in my studio working on a painting, and the sun started going down. I saw how pretty the sky was and felt sad that I wasn't outside painting, and I finally decided to do something about it! I don't have the greatest view from my living room window, but enough was enough! I turned my easel around to face the window and grabbed the first little canvas I could get find, and I painted furiously for about fifteen minutes. When the light changed too much, I grabbed another canvas and had another 15 or so minutes before all the light was gone. Somewhere in there I yelled for my long-suffering husband to grab my camera and take a few pictures for me.
Here's the second painting I did.
After it dried the next day (thank you, Los Angeles heat), I painted over it, using a photo to remind me what it looked like.
I have to remind myself all the time that painting is all about designing and distilling, not just copying what you see. I don't necessarily get inspiration from this scene with all the distracting details, but there is a lot of good information to grab and use for your own composition.