The query for this type of nonfiction will end up looking very similar to a novel query, especially if you’re writing a memoir. Include these elements, in no particular order (except the closing):
If you have confidence about the compelling nature of a personal narrative, start with that. Example: “When I was eighteen years old, I moved from my hometown in Oregon (population: 7,500) to live with the most powerful man in Hollywood and be a nanny to his three children.”
Whether you’re writing memoir or nonfiction narrative, you need to boil down your story to these three key elements:
What does sizzle mean? It’s that thing that sets your work apart from all others in the genre, that makes your story stand out, that makes it uniquely yours. Sizzle means: this idea isn’t tired and hasn’t been done a million times before. When it comes to memoir, there are a lot of tired storylines out there. In this agent roundtable on memoir in Writer’s Digest in 2010, you can get a feel for what makes agents’ eyes glaze over:
Sometimes great stories or manuscripts can fail at query stage because there is no life, voice, or personality in that query. Sometimes so-so hooks can be taken to the next level because they convey a liveliness or voice that is seductive. You want to be one of those seductive writers, of course—this becomes crucial for memoir, which tends to sell on the basis of voice when you’re not a celebrity.
But the honest truth is that a good number of nonfiction narratives have been conceptualized or executed in a way that makes them unsuitable for the commercial market. I comment on this further in Common Reasons Nonfiction Books Don’t Sell and Why Your Memoir Won’t Sell.