First day - walked around town sketching several spots (in the rain.) We were looking for an interesting view as well as someplace we could paint without getting wet if it rained all three days. Here is the chosen spot and the sketch I did on the first day:
The second day we worked on adding a rough sketch to canvas and starting out with under-painting (which I had never heard of before.) Basically you choose any color you want and just start filling in the shadow/dark areas with color. The oil paint is thinned with turpentine to make it watery. Once you have the darkest colors filled in - you choose a different color and paint the middle dark tones. The colors don't matter because the next step will be painting over top with more realistic color choices. My instructor called this day drawing with paint.
The third day was the most intimidating because I knew I didn't have much time left to finish the painting before I needed to head home. It was nerve racking to choose what colors to use. Another trick that I learned was to take each color and make three shades on your pallet using more and more white. The three shades help the painting look more real when you think about light hitting the building or the shadow of the trees.