Determine the relevancy of contrasting the two subjects of the essay. If the professor has set the subjects, the reason for contrasting them still needs to be established within the essay's introduction. Consider what new ideas can come from placing the two in opposition.
Research thoroughly both subjects. Chart the similarities as well as the differences between them. Contrasting needs not obscure any similarities. In fact, having comparable traits will distinguish those elements that remain dissimilar. Do not let any patterns you may discover along the way influence or stop your research.
Organize the differences between your subjects. Consider whether some of these differences can be combined thematically. Based on the subjects' dissimilarity, how do the two relate to one another? For example, if the two are arguments, does one complicate the other? Does one expose a flaw in the other? If so, let the better argument focus the essay. Use the differences between the two arguments to highlight how distinguished one is over the other.
Draft an introduction that includes your thesis, a single sentence that clearly states the essay's central argument. The thesis should also suggest the ways in which the essay defends, or illustrates, that argument. The introduction should also include whatever background information will establish the importance of contrasting the two.
Explain why one subject remains better than the other. Make sure that the argumentation is sound. Provide clear evidence for every assertion. Properly quote and reference your sources. Avoid what writing teachers call "logical fallacies," or flaws in reasoning that will weaken the essay. (See Reference 2 for a list). One logical fallacy is the "slippery slope," which concludes that based on one premise a series of hypothetical yet inevitable events will occur. This fallacy equates the first with the last premise.
Conclude the essay with a summation that reinforces the strengths of its argumentation and restates the thesis. Move this to the beginning of the essay and revise it so that it properly introduces the essay's material. Typically, a thesis and overview of an essay come into better focus for a writer after he has completed the process of writing its first draft. The conclusion often provides a stronger version of an essay's introduction.
Revise the rest of the paper and rewrite a conclusion. Verify that all quotes are properly referenced in the format specified by the professor.