Here are some demos that I recently did. The first one is a landscape that was just out of my head without any reference. I have nothing against reference, in fact I am very much in favor of it. I just mention that I had no reference as a disclaimer for why it isn't better.
The next two are digital portrait studies that I did from life of a couple co-worker friends, Emily and Dillon, who were nice enough to sit still for me. I tried to do an approach similar to what I would do with real paint.
Also, I am not very good at talking while I'm painting (or at any other time for that matter) so I decided to borrow the audio track from someone much more experienced in painting demonstrations than myself. I think his commentary is probably at least as instructional as mine would have been, plus something about his voice just makes me feel happy. Special thanks to Tom for help with these videos.