• The most important suggestion is for you to purchase a good “how-to” book on writing nonfiction book proposals so that you can create a professional looking package. See Barrett Books' Suggested Reading .
• Briefly describe in a query letter the book you want to write. In an overview, go into further detail, making sure you reflect the tone and style of the final book.
• Don’t assume that an editor or agent will know there’s a strong link between your book and a current bestseller or any other market tie-in. However, be sure to state how your book is unique.
• If you are close friends with a film producer or famous author; have won a Pulitzer; can get multitudes of people to buy your book because you belong to a major book club, have lots of connections or are a public speaker; if your book has an immense and identifiable audience, or if you already have quotes from credible sources…mention it, and mention it early in the proposal.
• Your idea should have universal appeal—it should be able to sell at the very least 10,000 copies to generate the interest of a major publishing house.
• A good book proposal should answer the question, “Why should this book be published?” Propose a simply stated thesis that the book will prove or answer.
• Research the success of similar books and include the facts and figures. A previously published book may approach the subject differently than what you intend. It is imperative that you mention similar books that are in the marketplace and why it will not be a problem for your book idea.
• A complete proposal should be about 25-30 pages long, including a sample chapter. If possible, mention how long the book will be (100,000 words or 300 pages is average) and how long it will take you to write.

A Complete Proposal Includes:

• Brief cover letter
• Title page
•  Hook followed by an overview of the project
• Marketing analysis
• Brief description of competing books
• Half-page narrative biography
• Table of contents
• Narrative description of each chapter listed in the table of contents
• Estimated book length and delivery date
• Sample chapter