It is not that long ago that I decided to paint portrait from life. The reason to paint from life rather than from photograph is that is more challenging because your subject matter is not still and the colour are more truthful then in the photograph. So you learn yourself to be ok with a moving subject and learn to see colour properly.
And since I'm so slow in process of painting and I don't have enough confidence to invite any sitters into my humble room to keep them moveless for several hours yet I'd decided before I'd ventured to paint with oils someone else to put a mirror in front of me. The great example of this approach is Rembrandt - Throughout his life he made a copious amount of self-portraits.
I began with heavily stained canvas of burnt umber - it was an unpleasant endeavour from past that I'd had to scrape down (therefore I don't want to talk about it :-))
You can see the settings while I was painting and final painting down bellow. Since I've done it throughout evenings after work it is somehow on the dark side - I have to rethink lighting setting of my work place :-). The final picture is really really dark. But I think it conveys some kind of mystery at least about a person depicted. If you don't stick the picture under a strong daylight the face is barely visible.
Me painting myself...
Final painting - Nocturnal creature (oil on canvas 11x14 inches)
Best wishes to all of you, Pete