Take your first steps forward by breaking the assignment into do-able pieces. Once you have ideas about what you want to say, develop a strategy. Think about what research you'll need to do. Sketch a plan. That plan is important because it begins the outline of your essay.
Research is crucial.
Begin with basic reference tools. Check the library. Wander through sections of bookstores or library stacks. Check Web sites and UCL's digital library. Ask reference librarians for assistance.