Stetch out your picture. Place tape (masking tape works well) on the areas that you wish to remain white. We did that on the roofs of the barn. We have overlapped many of the shapes (about 3 out of 4 or 75%). Then paint your sky and foreground. Paint the buildings and trees. Be sure to add your shadows. Remember that painting dark colors next to your light colors tend to make the light colors pop. Give it a try and see what you can do and have fun.