I would like to add that you might consider the importance that might be placed on Ponyboy's need to stay true to himself and withstand outside influences, especially societal and financial (which are related).
well if you have read the novel or seen the movie, check out the part where Johnny writes his last letter to Ponyboy. It says exactly what that poem meant and what he wants Ponyboy to do. good luck on your essay~
I would begin by brainstorming. Consider the following:
What does "stay golden" mean? What would Johnny want Pony Boy do or become once he is gone? What hopes might he have for his friend? Consider their relationship and what the boys have meant to on another. Once you have some ideas, your essay could focus on more specific instructions that Johnny might give his friends. Good luck with your essay!