What Is the Chicago Manual of Style?
As a self-published author, you may have never heard of the Chicago Manual of Style, but you can bet that any editor you hire will have. It's the book pubisher's bible that lays out rules on everything, from how a book should be organized to how to use each punctuation mark. A professional editor will follow it to make all the text in your book consistent. To save your copyediting budget some money, follow these basics, because the cleaner your book comes in, the less time it takes to edit, saving you time and money. If you don't know all the grammar rules, it's OK; that's why you're hiring an editor.
Front matter: Do a little research and find out what information belongs in the preface vs. the introduction (or whether you really need to have both) before it gets to the editor. Is your first chapter really an introduction instead?
Serial comma and semicolon: Chicago follows a punctuation usage called the serial, or Oxford, comma. When you have a list of items in a sentence, commas separate each one, and a comma is inserted before the "and" or "or" in the list. When elements in your series have internal commas, they are separated by a semicolon to avoid confusion. Sounds simple, right? It usually is. Periodicals, however, usually follow Associated Press Style, and it does not include that last comma before the conjunction in most instances. If you're writing a book, your editor will likely follow Chicago Style and use the serial comma unless you specify otherwise.
Capitalization: Although your word-processing software has a shortcut that will capitalize every word in a headline automatically, Chicago Style requires that all conjunctions, prepositions, articles, and the like are lowercased. Your editor will go a step further and make sure that your A-level headlines are formatted or styled differently from your B-level subheads if your book will be going straight to design.
Quote marks: Commas and periods go inside quote marks, except in cases of computer code. Semicolons go outside, and exclamation points or question marks go inside or outside, depending on context.
Hyphens: Compound nouns, adverbs, and predicate adjectives all follow different hyphenation rules. Trust your editor to know and apply these rules correctly and consistently throughout your manuscript. For example, "A part-time worker is one who works part time." It looks inconsistent, but the first usage is a direct modifier and the second is a predicate adjective. (This sentence wouldn't actually make it to print, as it's redundant and circular.)
Numbers: Chicago Style generally spells out numbers one through ninety-nine, though if your text contains a lot of numbers, you may wish to use the other allowed number style, which spells out only one through nine and uses numerals for 10 and above. There are exceptions to the overall number rules, of course; for example, in rule 9.7, Chicago allows small numbers to be numerals for consistency in a sentence: Sheila had 113 game pieces, and her brother had only 6.
Dates: Chicago Style spells out days and months, uses parenthetical commas around dates, and does not use "th" after the date numeral. For example: Monday, February 27, 2013, was a gloomy, cold day. In contrast, AP Style allows some months to be abbreviated.
States: Chicago Style spells out names of states in running text (addresses and charts may have a different style). It differs from AP Style, which uses abbreviations for most states (different than postal abbreviations).
References: Generally, citation information goes in this order: Author, Title, where published, year (though in author-date style, the year moves up by the author name). In a bibliography or reference list, citations are organized alphabetically by author last name. Web links might not always have an author listed, and the organization may stand in for the author. Include your access date, in case the article is updated after you look at it, and the link at the end of the citation. Click here for a helpful resource.
If you see something that you think was missed or changed incorrectly by your editor, ask questions before reverting the change. A good editor will be able to explain the grammar rule or cite the exact Chicago rule number that she is following to edit your text.