Your first draft is done!
Now the real work begins.
Go through your story on your own several times looking for grammatical errors and plot holes. Make your manuscript as polished as you can, then pass it onto your wonderful beta readers. I definitely recommend this because they are not as emotionally invested in the story and may find things you miss. Beta readers can be your friends and family, but I also recommend putting the word out to Beta readers via Goodreads or Twitter. Some offer free services while others charge fees. This will provide a viewpoint from someone who doesn’t know you personally and therefore won’t worry about hurting your feelings.
Seriously, though, get as many people to offer feedback as you can. The more people who read your book, the more perspectives you have, the more people who can find errors, and the more people who will anticipate your book’s eventual release.
Professional editing is next. Should you do it? Is it worth it?
If you can afford it, and there are affordable editors out there, absolutely have your book edited by a professional. I cannot tell you how invaluable I found my editor. He pointed out a lot of plot and character points that I would’ve never considered and it made my story a thousand times better. Your editor knows the market, knows the rules of writing, knows the genre, and will make sure your book “follows the rules” so to speak. I received a 40 page wrap-up of my novel with extra links to reading materials and tips. These notes included character notes, things to resolve, style and filtering tips, word usage (20 pages worth), world building notes, and formatting help. My editor was so detailed he could point out if I missed anything that was not accurate to my time period. I also received marked up copies with in-line notes and clean copies. I spent hours going over the story and doing final edits after. This copy I went through once more before passing it along to my husband for a last read through. This is the FINAL draft.
Editing could arguably be just as strenuous as writing a first draft. Several times I wanted to give up, start from scratch, burn my manuscript, and question all my life choices. But in the end, editing will transform your book from a chunk of coal to a diamond.