Write out the text that explains the sequence of actions for a given Use Case. Then, find nouns and verbs. While this is an oversimplification, nouns become classes or variables and verbs become methods or associations. You can certainly make up your own conventions, but here is something to try. First identify nouns by formating them with an underline and tag verbs by bolding them. After you have constructed code by using the nouns and verbs you identified, use additional italic formatting, so you can track your progress. Thus, you can tell which parts of your use cases have been coded somewhere and which have not. Try to use verbs to describe all of the responsibilities that you think an object has for other objects.