Hire a professional copy editor. Some people are surprised when I tell them that I had the manuscript for Baby Grand professionally copy edited.
“But aren’t you an editor?” they ask.
“Yep,” I say. “And as an editor I know the importance of a good copy edit.”
Copy editing, or line editing, is going through a proof or manuscript, line by line, in order to find errors (grammatical, continuity, etc.). Baby Grand just went through copy editing and, as it turns out, was relatively clean (as it should be, since I am, indeed, an editor), but the copy editor did catch quite a few formatting and grammatical (e.g., en dash vs. em dash) issues and asked astute questions with regard to plot and characterization. As I clicked through the manuscript, I kept thinking how happy I was to have had this critical eye go through the copy one last time.
Keep in mind that copy editing is a professional service. It’s not really something you can ask your friends to do for you. On the other hand, anyone can be a “beta reader,” who is also someone who reads your manuscript for errors, but that person will probably not be as meticulous or familiar with style guides as a professional. Both have their place and can be very helpful in making your manuscript the very best it can be.
Professional copy editing or proofreading rates vary per project, and copy editors may charge you by the hour or by the page. For a 300-page manuscript, you may pay something like $600 to $1,000, but, again, pricing depends on the person or company you use and the services needed. It’s probably a good idea to ask around, too, and see if any of your writer-friends can recommend a copy editor whom they found to be affordable, yet thorough. After seeing the kinds of things my copy editor found that escaped my eyes, my advice is not to skimp on the copy-editing. It’s worth every penny.