The first or introductory paragraph should contain a thesis statement, which is a concise statement of the argument to be developed in the body of the essay. Two keys to writing a persuasive thesis are thoroughly understanding the question and the text it refers to, if it is a literary essay. If you do not understand the text the question is based on, read it again with a study guide or consult a friend or teacher.
The thesis needs to be simple enough to be contained in a paragraph, but complex enough to be further developed in one or more paragraphs totaling around 800-1,000 words in length. The first paragraph should set an authoritative tone, convincing the reader that you know what you are talking about. This can be done by addressing the big picture -- for example, story and circumstance of a literary text that is relevant to the argument of the essay. Avoid unfocused, indecisive and generalized comments by confidently using the text to advance the argument.
Paragraphs between the introductory and concluding paragraphs should develop the details of the argument, one point for each paragraph. Each point should advance the argument and should do nothing more. Each and every point should also be supported with evidence. As a general rule, one quotation from a literary text should be used to support each point in an argument. It is often an effective technique to embed quotations from a text into your own sentences.
Avoid just retelling the story of any text. A literary essay should discuss how authors use language and literary techniques. This can be done by addressing how an author uses language to build tension or mood, how he uses it to reveal character or setting, and how the language advances the theme of the work. Language, structure and style of quotations should be discussed.
The conclusion of an essay is used to restate the argument of the essay and briefly summarize the evidence to support the conclusion, along with a comment on its wider implications and relevance. New material should not be introduced in a conclusion.