Underpainting

One of the first things I learned in my oil pastel class introduction was how to create the under painting. There are various ways to go about an under painting in oil pastel but the easiest and most immediate is to block in shapes with color, use the side of the crayon and apply the color all over the surface. Next, use a non-toxic product called "Res-n-Gel" available at most art supply stores. Take a clean paper towel and just rub in a small amount over your blocks of colors and eventually it will all smooth out and create a wash effect. The colors should dulled or grayed down at this stage so you can apply brighter colors on top. I find it's very important to use your darks at this stage because in this medium you usually want to work from dark to light. I have seen some artists use turpenoids to create under paintings and washes. They seem to really break down and smooth out the OP's, but they are toxic. I personally think that the Res-n-Gel does what it needs to without the toxic effect.