FREE: On Writing Well, Nonfiction Writing Guide

It talks about basics to consider when writing, such as style and audience, methods and strategies of writing, and then nonfiction specific parts, and some views on writing memoir, travel, interviews. It talks about business writing and some other forms of nonfiction. Near the end of the book it includes some chapters about the use of voice in nonfiction and decisions to make when writing nonfiction. It is an older book, but the writing principles still hold true and I think it is a useful guide to learn more about writing.

This book is one of the best on writing. Good luck!