You can divide the problems up and take care of them separately. Using an underpainting is a great way to do this. In this way we do not think about color until later. We think only about drawing and composition at first. Getting the right tonal values.
Many people simply use black and white for their underpainting.
Some people do a very rough lay-in. Other people do a more complete job on their underpainting. If you look at the paintings in museums, you will sometimes see the underpainting showing through the layers of paint on top. Sometimes the painting wasn't finished and the underpainting is very clear. Look at the illustration to the left.