If you write nonfiction, blogging your book before you publish can be a great way to gain an audience and test out your ideas. However, blogs and books are two different writing beasts. You need to understand the purpose and structure of both, so you can transition smoothly from one to the other.
What Is a Nonfiction Blog?

A blog is a place for you to share your knowledge and experience with others. If you’re writing memoir-style nonfiction, your blog is similar to a public journal. If you’re writing nonfiction that teaches something, your blog is more like a public guide. Either way, you are presenting your knowledge and experience in a casual, episodic way. That means posting on a schedule.
Each blog post should be a complete story or tip and is likely shorter than a book chapter. Blog readers are looking for quick, easy to implement answers to their questions. The tone and structure you use when writing a blog should be causal and conversational.
What Is a Nonfiction Book?
A nonfiction book also shares knowledge and experience, but it promises a bit more too. If you’re writing a memoir, you’re delivering a story with some sort of message or life lesson. That means you’re more selective of which experiences you choose to include. If you’re writing a nonfiction book that teaches something, you’re helping your reader reach a burning desire. After reading your book, they should be able to make a life change or have a more in-depth understanding of your subject matter they can put into application.
Book chapters are often longer and more detailed than blog articles, so you have the space to fully explore your experiences and topics. Book readers are looking for in-depth knowledge they can use, but they won’t be able to implement everything immediately. A book has a more formal tone and structure.