There are some common and annoying mistakes which may significantly harm your grade. However, you can avoid those grade lowering mistakes by completing the following checklist:
Include an introduction and a conclusion no matter which method you choose to structure the body of your essay. It is often helpful to write the introduction and conclusion after you have written the body of your paper. A good introduction will introduce your subject in a general fashion and then begin to narrow gradually, ending with your argument. Think of it as a map of the rest of your essay. The conclusion should return to the ideas with which you began your essay and restate your argument. It should leave your reader with a summary of your main points as well as your argument.