Read and reread the material. This includes highlighting (or making notes on index cards - one idea per card) key passages and specific quotes while reading to help you develop a strong and supported thesis statement.
Determine a thesis statement. A thesis statement is the anchor of your paper and should be a strong answer to the prompt. All of you arguments throughout the paper should support your thesis statement. For example, if the prompt asks you, "Who is the hero of the story and why?", your thesis statement should clearly state who you believe to be the hero in the story and the main reason why. In most cases the thesis statement is a one sentence, succinct answer to the question.
Create an basic outline. While your thesis statement is the main idea of the paper, you must derive supporting statements from the material to prove your thesis. Extract the strongest evidence of your thesis statement from your reading notes to structure the paper.
Chunk your paragraphs. Chunking is a methodical way to organize your paper. Start with a topic sentence that introduces the main idea. Follow it by a concrete detail which is your quote or paraphrase from the material (be careful not to fill your paper with paraphrase, though). Support the concrete detail with three sentences of commentary that reflect your ideas and support your thesis. Repeat this formula for all of the paragraphs in that section, ending with a closing sentence. Repeat topic sentence through closing sentence for each section.
Edit content for flow. After completing a first draft of the paper, read through it completely to make sure all of your arguments support the thesis. Pay close attention that you chose strong examples from the reading material and that your commentary explains your examples.
Cite your references. Whether you just use the book or reading material you are given for the assignment, or you use multiple sources, make sure to cite them properly throughout the paper. A good source for citing formats is the MLA Handbook.
Ask for help proofreading. Editing and reediting a paper can make you blind to otherwise obvious grammar, spelling and syntax errors. After you feel the content is where it should be, have someone else proofread the paper before you consider it finalized.