It doesn't matter how good the body of your essay is if you start off on the wrong foot. First impressions count, especially when it comes to your grade. A bad opening can lower your grade, no matter how good every other part of it is. The opening convinces the reader that he or she should keep reading. The opening further convinces the reader that you have something interesting and important to say. It is arguably the most important part of your essay.
Write the body of the essay first and the introduction last. This way your opening will be a more accurate representation of what the essay is about.
Open the introduction to your essay with a hook to grab the reader's attention. Some ways to do this include using a relevant quote, a provocative assertion or a thoughtful question.
Give a context for the overall essay and subject matter to be discussed so that your reader begins to have a solid idea of what to expect.
Move from the general to the more specific as your opening paragraph progresses.
End your opening with your thesis statement, usually a one sentence that clearly states the point of the essay.