Scan the title, author and table of contents. Get a feel for what the book is about from this information. If the author or subject matter is unknown to you, some background research might be in order.
Read the book carefully. Take note of the author's thesis, the kind of evidence she uses, and the overall organization of the text. Determine the intended audience while you consider your own responses to the book's elements.
Construct an outline of the book. Summarize the thesis, then briefly summarize the contents for each chapter. Make note of your responses to particular arguments or sections.
Make the skeleton of an outline for your review. Decide at this point how extensive and detailed you want your finished product to be. Most professional reviews published in journals are 500 words or less.
Fill in the details of the review outline with information from the book outline. Remember the elements of nonfiction essays: introduction, body and conclusion.
Write an introduction that includes a concise summary of the book's contents and arguments. Be sure to restate the author's thesis.
Draft the body sections by discussing elements of the book you found most important or relevant. At this point, you can include your own responses and judgments of the author's work. For example, you might criticize the author's interpretation of a certain piece of evidence, or you praise the writing style of the book as a whole.
Conclude the essay by either recommending or not recommending the book to its intended audience. In other words, give it a thumbs up or thumbs down.
Read over your review and edit for misspellings, grammar errors and organization. Reading aloud is an effective way to hear mistakes or awkward writing that otherwise goes unnoticed.