Use a letterhead or put your name and address in the top right-hand corner. I don’t advise queries be sent by e-mail.
Address the query to a specific agent or editor.
Start with a “hook” or snappy language or something to grab the reader’s attention immediately.
In present tense, state precisely and succinctly what the book is about. (Think in terms of how a TV show is explained in TV Guide.) For example: Out-of-work lingerie-buyer Stephanie Plum blackmails her cousin into hiring her into the unlikely position of bounty hunter.
In a sentence or two, writing luck describe why you are “the one” to write this book. For example, you worked as a homicide detective for fifteen years in Los Angeles or you are a forensic medical specialist.
Keep the query short–one page.
Mention the proposed length of the book.
End by asking the agent or editor if he would be interested in seeing the full manuscript.
Make sure the letter is grammatically correct. (Remember: Don’t count on spell check alone to catch every error. You must read it over).
Use heavy, twenty-pound bond, which is easier to handle than lightweight paper.