1 Historical review: Some topics are better understood if a brief historical review of the topic is presented to lead into the discussion of the moment. Such topics might include "a biographical sketch of a war hero," "an upcoming execution of a convicted criminal," or "drugs and the younger generation." Obviously there are many, many more topics that could be introduced by reviewing the history of the topic before the writer gets down to the nitty gritty of his paper. It is important that the historical review be brief so that it does not take over the paper.
Plan B: Use Plan B if you have only a few, larger similarities or differences. After your introduction, in the next paragraph discuss one similarity or difference in BOTH works or characters, and then move on in the next paragraph to the second similarity or difference in both, then the third, and so forth, until you're done. If you are doing both similarities and differences, juggle them on scrap paper so that in each part you put the less important first ("X and Y are both alike in their social positions . ."), followed by the more important ("but X is much more aware of the dangers of his position than is Y"). In this format, the comparing or contrasting goes on in EACH of the middle parts.