- Have you edited it thoroughly by yourself? Check your facts. Check for consistency. Check for grammar, sentence structure, and spelling issues. Physically go through and verify that it as good as it can get. And never ever rely on a spell checker or grammar checker! While they can help, they are notorious for missing things or correcting things that don't need corrected. They are a great place to start, but you need to be independent too.
- Have you developed a title? You had a working title, sure, but is it what you really want to call it on the open market? Does it capture the point of your story? Will it attract the right type of reader? Carefully examine the reasons why you are picking this particular title and, if it doesn't work, don't be afraid to scrap it and start finding a new one. It can be scary to have an untitled manuscript this close to completion, but it will benefit you in the future if you take the time to know it is a 100% perfect fit.
- Does your book have a blurb? Not only does this paragraph or two of information need to contain a summary of your work, it needs to pack a punch. It needs to be more aggressive than just "drawing" your reader in; it needs to grab them by the wrist with an iron grip and yank them into it! This can be difficult, especially since you are so close to the work, so make sure you have plenty of honest reader friends look it over. If they wouldn't buy the book immediately after reading your blurb, then it isn't doing it's job.
- Do you have a good cover? If you are epublishing, then a cover is one of the most important things you will develop in this stage. The phrase "Don't judge a book by it's cover" is irrelevant in the ebook world. Trust me, your potential readers will take one glance at the thumbnail of your cover and, from that information alone, decide if they want to continue or click away to other things. If needs to not only represent your book well, but it needs to be well done. No cruddy artwork, no blurriness, no hard-to-read wording. It needs to be good, solid art. Not an artist yourself? Expect to find someone that is to do it for you.
- Has a professional editor looked it over? Even if you are an editor as well as a writer, you still need a fresh set of eyes. And no, your friend from down the street doesn't count (well, unless they really are a professional editor, but for the sake of argument let's say they aren't). Most people in your life will take it easy on you or will miss something important, like a fact being different on page 101 from when it was mentioned on page 1. Find someone willing to give it the attention it deserves.
- Have you made yourself visible online? Twitter, Facebook, Goodreads, your own blog, your own website, forums, Google+, and many more websites and networks can help make you more accessible to your future readers. When you finally publish, people will want to research you. Give them places to go where they can find out more about you, your work as an author, other things you have published, and any other information you are willing to share. The more they know you, the stronger the connection, and the more likely they are to purchase what you have to offer. And don't forget to interact!
All done? Now, you may continue!