When you have the sketch, you can play around with different ways of breaking up the class. To do this, circle groups of features. When you circle features, the lines that you cross can define the interface of a new class. As you circle, try to come up with a class name for each group. Frankly, aside from anything that you choose to do or not do when you extract classes, this is a great way of increasing your naming skill. It’s also a good way of exploring design alternatives.
Feature sketching
