Below is The 6 Essentials for Submitting Your Novel to Agents, from Writer’s Digest.
Employ the basic query format: a 3-paragraph letter with a salutation, book description & bio.
But if you’re really confident in your letter-writing prowess, feel free to mix it up! The best letters convey the tone of the book, and my favorite query letter of all time (Gennifer Albin’s letter for Crewel, which is coming out from Farrar, Straus and Giroux Books for Young Readers next fall) actually started with a few lines from her preface, which captured the spirit of the book perfectly. (Just be sure to include the other elements on this checklist, regardless of your approach.)
Explain why you’re approaching that particular agent.
Remember all that research you did in figuring out who to pitch? Here’s your chance to use it by explaining that you’re submitting your work of X genre because you saw that the agent represents it. If you want to go one step further, list one or two specific authors the agent reps whose books you love. (Just be sure you’ve actually read those books so you can discuss them if the agent brings them up!)
Give a brief description of your book.
We don’t need a full plot synopsis—think of this as a thesis statement or an elevator pitch. Give a sense of the overall arc of the book and the broader themes it touches upon, rather than listing everything that happens.
Provide a short author bio.
At the end of your letter, include a one- to three-line bio, describing who you are and why you wrote this book. Just as you wouldn’t mention all the skeletons in your closet on your first date, don’t overshare by telling us that the work you’re submitting is your third unpublished book or that your mother lives in Kalamazoo. Simply give us the parts of your bio that are charming, impressive or directly related to the matter at hand. Wow us with your strong publication history, your distinguished educational pedigree or your unique, relevant life experience.
Make sure to include your contact information.
You’d be amazed at how many people don’t. At minimum, list your e-mail and phone number so that if we’re excited about the submission (or if we have questions) we can ring you up.
Be prepared for the next step before submitting anything.
Make sure you’ve got all the material an agent might request (a finished and revised full manuscript, information about your previous publishing history and a synopsis) on hand and at the ready to send, should an agent ask to see that material after reading your query.
More information for writers available at Writer’s Digest.