1. You should avoid the temptation to hire someone to edit your first draft.
I know you’re really excited that you finally finished that book! I’m happy for you … you should be happy for you. Celebrate it! But don’t send it to an editor yet. Put it away for three weeks and then reread, making notes on its strengths and weaknesses, asking yourself what’s missing, and flagging places where you find yourself skimming. Then rewrite the manuscript at least once—twice is better. Don’t bring in a professional until you have made the book the best you possibly can on your own. At this stage, you are still best equipped to take your book to the next level. Only when you’ve taken it as far as you can on your own will you get the most for your money in hiring a freelance editor. Which brings me to a related point:
2. An editor is not a ghostwriter.
It’s not uncommon for nonfiction clients especially to believe that because they have an outline, research notes or interview transcripts, their book is “almost done” and ready for an editor. But if you’re looking for someone to take any of the above and shape it into a manuscript, what you want is a ghostwriter. A nonfiction editor won’t do extensive research for you. A fiction editor is not going to invent characters, flesh out dialogue or write missing scenes. If you hire an editor to do a ghostwriter’s job, you’ll surely be disappointed with the outcome.
3. Your editor is likely to feel more invested in the kind of book she enjoys reading.
Your editor should be familiar with the conventions of what you write. You don’t want her suggesting, for instance, that you include an explicit sex scene in your Christian women’s fiction. Even more important, you want her to like your book enough to want it to be the best it can be. If a prospective editor seems lukewarm from the start about your manuscript or genre, walk away. Find an editor who exhibits genuine excitement about your project. This doesn’t mean that if you’ve written a young-adult paranormal vampire romance you need an editor who specializes solely in that genre. But it does mean that you don’t want an editor who hates teenagers, hates vampires and hates love stories.