Last night was one of those nights... I was exhausted, and the first drawing I started (which I will not post for fear that you'll never come back and lose all faith in my abilities) was AWFUL> SO I took a break and moved to a new spot in the studio, drawing Denise from another vantage point - creating the black and white drawing using charcoal and a little water on a gessoed masonite board.
So then I went back to my first drawing, hoping that with the fresh perspective I could solve it...no. Still didn't work.
Realizing that I just didn't have the brain power to fix the first drawing, I grabbed another sheet of paper and my nupastels and sat on the floor to draw looking up. Much better. I still have to define a few moments on the face, soften the (too similar) breasts, and maybe add a bit of color to the background.
Bottom line...don't beat your head on the easel - if a piece isn't working, don't waste precious time with the model. Always bring a few extra surfaces, and start something new.