The process of finding the right editor for you and your manuscript can be challenging. For one, there are many of us out there. Two, you need to know what you’re looking for. Here are my top tips to put you on the right track.

1. They should offer—or at least be willing—to provide you with a complimentary sample edit. This gives you an idea of the types of things they’ll note and how thorough they’ll be. That’s not to say it will cover everything, but it will at least give you an idea. They may request or edit anywhere from a few pages to a whole chapter; it will vary by the editor. It may also depend on the manuscript, so the same editor may want more for a different project, depending on the circumstances. 
2. While this is part of the sample edit, it’s important enough to warrant its own point: If you get your sample back and it only has a few things noted, be wary. You may think, “I nailed it!” But it’s more likely they got lazy or aren’t qualified for the job. (That’s not to say it’s not possible to have such clean copy; it’s just not likely.) With the second book I ever sample edited, the author later said that one of his main reasons for hiring me was because I noted far more than other editors. And it’s not just corrections; it’s suggestions/guidance. A good editor wants to help you make your book the best it can be. Their edits should convey that.
3. Be sure they know CMOS (Chicago Manual of Style), the style standard for book publishing. While you may choose to go against some of the CMOS guidelines, your editor should know those standards to help guide you and let you know what publishers may change. Plus, it gives a baseline for consistency with editing.
4. Get a feel for their personality. You may see some of this in email exchanges or sample-edit comments. Be sure you are comfortable with your interactions and how the editor words things. Make sure you won’t feel weird asking questions or having a discussion about an aspect of your manuscript. Editing can be a sensitive process (you’re letting someone else into your baby’s life, after all!), so having the right partner for it is important.

I’m always happy to answer questions about the process and give insights into how I work as an editor. Feel free to contact me.