When proofreading a document, you should first read it slowly out loud to determine whether or not it communicates its message. If the title or the introductory paragraph do not clearly signal the intent of the paper or if the paragraphs that follow do not naturally flow from that introduction, you might want to rewrite those parts of your paper. 

Once that is completed, you should search for errors in spelling, word usage, grammar and punctuation. Proofreading is the last step between you and the reader, which is why it is necessary to take the time to ensure that your writing is accurate, clear and easily understood. 

Professional editors can proofread your document so the final product is professionally written, precise and easy to read. It is important to carefully proofread all written material. Proofreading is an essential part of the writing process.