Here I have started to lay down color to provide the under painting for the final colors. I put down strokes of pastel color that I figured would be complimentary to the final colors or would fill in some voided areas. I have done this before, but this time I used stumps to drive the color into the board with more authority. This is a good sub surface to work over, but you have to pay attention to what our doing so as not to cause a muddy situation when putting down the finale layers of color.