The first paragraph of your essay should introduce the work of literature about which you are writing, introduce the main idea or message about the work that you are going to present in your essay, and should briefly list each of the points you are going to present about the work. Depending on your assignment, you may be describing the characters, giving details about the action in the plot, comparing two works against each other, or some other topic. In your introduction, give a preview of each of the pieces of information you will develop in the body of your essay.
In the body, each of the points needs to be presented in a separate paragraph (or more, depending on how much detail you are presenting). The first sentence of the paragraph is your statement of the point. The following sentences provide supporting details to prove your point, additional information to explain why you are taking this position, or explanation of why this is significant to the work of literature you are analyzing. Organize the paragraphs about your points so the information is presented in the same order as you introduced the points in your introductory paragraph.
End your essay with a concluding paragraph that summarizes the points you have made and relates them back to the main idea you announced in your introduction. A fun and short way of summarizing the process: "Tell them what you're going to say; tell them what you need to say; tell them what you've told them."