Here's how I start a painting, with a grisaille in acrylic to work out the composition and distill what I'm interested in visually about what I want to paint, in this case the interior of a K-Mart with post-Valentine's Day animals on sale. This Drawing determines the size and shape of the surface I'll do the painting on, rather than starting with a shape and fitting things into it.
This is the underpainting, done in what the Dutch 17th Century painters called a 'dead color' layer. The only colors are black, raw umber, and white- although in this case I've added some color to the fleshtones. I've found this step to be really useful in separating out the values (darks and lights) from the color. I started doing it because it looked like fun to keep the palette limited and then discovered how useful it is.
"1000 San Fernando Road" 42' x 69" Oil on Canvas over panel
Here's the finished painting. I like to take this long, old, slow way of looking to bear on these places places we've made not to be looked at quickly or not at all.