How to become a book proofreader?

There are no formal education requirements to become a book proofreader, though some employers prefer candidates with an associate or bachelor's degree in English, communications, journalism, or a related field. Brush up on your grammar, spelling, and punctuation skills so that you can identify errors in manuscripts quickly. Read different genres of books to become familiar with a variety of writing styles. Offer to proofread articles and other writings for free to demonstrate your skills and build a substantial portfolio. You may seek proofreading positions at publishing companies, or you may choose to become an independent contractor and work directly with authors and editors.