Book flaps are an art of sorts, because they have to hook the reader in, give a good idea of the story, but keep from spoiling anything too important. It takes some work, and even good writers can write awful book blurbs.
The good news is, if you're at the publication brink, you probably already have a good idea how to write a book blurb! How so? Well, you wrote a query letter, which has important pieces that can be taken out and tweaked into a book blurb. I find that the most interesting and best query letters walk the line between professional request and hooky exciting book blurb. As a matter of fact, when I'm writing a query, often I start by working on a book blurb, taking the idea and condensing it into the perfect summarized hook. Then I work it into the query letter. Practice makes perfect in this case, but the main point to consider is why would you read this book? Who are the characters? What is the setting? What's the situation? And most importantly of all, what is at stake? Give the readers a reason to care, and your book flap will be a success. It's all about marketing. This is the business part of the novel process, and for many of us, that makes it the hardest. But it's also very rewarding.
For more tips on writing book blurbs, you can check out this link.
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