2. Analysis: Now that you have a good knowledge base, start analyzing the arguments of the essays you're reading. Clearly define the claims, write out the reasons, the evidence. Look for weaknesses of logic, and also strengths. Learning how to write an essay begins by learning how to analyze essays written by others.
3. Brainstorming: Your essay will require insight of your own, genuine essay-writing brilliance. Ask yourself a dozen questions and answer them. Meditate with a pen in your hand. Take walks and think and think until you come up with original insights to write about.