There are many ways to finish your pottery. The design should not stop once you have finished building. Be sure to consider how your work will look once complete. What color(s) should it be? Will there be detailed designs? Does your piece need to be food safe? All of these considerations should be made for each piece as they will direct your completed look.
Underglazes are a great way to add details to a project.
Under glazes can be painted on bisqueware or even greenware. They can be layered and allowed the artist to paint on clay in a more permanent way than paint.
Sgraffito is a technique where an artist covers greenware in a layer of engobe or underglaze before carving a design in the color. This technique can result in designs with nice contrast. Check out the Sgraffito for more info.