I have just blocked in the background.  This allows me to focus on the figure and the negative space. I always tend to work with a light wash initially and gradually add layers whilst thinking of light and shade.  As the painting progresses I add darker contrast to give the painting depth.  This painting has little subject matter other than the little girl and the leaves but that is exactly the point.  She was lost in the world of shuffling at the time I spotted her and I can still remember how happy it made me feel!