You should formulate your thesis statement—the central argument you`re going to make. The thesis statement provides focus and signals your position on the topic. It is usually one or two sentences long.
For this reason, it can be helpful to simulate the conditions of a timed exam before the actual day: pick a practice question, find some lined paper, set a stopwatch, and see how you do!
Some students react to the time pressure of essay exams by scribbling down their introduction as soon as they`ve read the question and figuring out their points as they go. While it might seem counter-intuitive, taking five or ten minutes before you start writing in order to draw up a plan will be an enormous time saver.
Do your research: Read primary and secondary sources and take notes to help you work out your position and angle on the topic. You`ll use these as evidence for your points.
For example, if you`ve been assigned a five-paragraph expository essay for a high school class, you`ll probably spend the most time on the writing stage; for a college-level argumentative essay, on the other hand, you`ll need to spend more time researching your topic and developing an original argument before you start writing.
In longer essays, you can end the introduction by briefly describing what will be covered in each part of the essay. This guides the reader through your structure and gives a preview of how your argument will develop.