Long, long ago - they tell me - all an author needed to do was write. And maybe go on a speaking tour from time to time.
Now, an author wears many hats. How many hats can one person balance on their head before their neck snaps?
First, there's the Writing Hat. You have to get that rough draft done, or your writing career will go nowhere.
At some point, you will probably need the Research Hat, even if you write fiction. If your story involves some military, how is it organized? What ranks does it have? If it's science fiction involving humans, you might research militaries throughout history, and extrapolate from what you've learned. If you're writing a fantasy about dwarves, you might study the tales about dwarves, and try to figure out how they might organize an army. (Hint: A dwarf army is not likely to have cavalry. At least, not a cavalry on something as big as a horse.)
Next comes the Self-Critiquing Hat. You go through your rough draft and make it better by smoothing out rough spots and inconsistencies, adding description and explanation where it's needed, making sure you've said what you intended to say. Actually, you wear this hat more than you wear the Writing Hat.
Next comes the Listening Hat. You ask for feedback on what you've written, and you listen to what they say. Maybe your hero's eyes changed color mid-book, or you use the same phrase over and over, or 3 out of 4 readers didn't understand the first half of chapter eleven.
Back to the Self-Critiquing Hat as you go through your manuscript, considering the feedback, whether or not to change anything, and if so, what's the best way to do that?
Many authors are opting to self publish, these days. Once they've gotten their manuscript as good as they think they can get it, they probably hire an editor, maybe a copy editor, possibly a proofreader, and some will even hire someone to format the manuscript into e-book and print templates.
Or maybe they don't. In which case, those are all hats they should make sure fit their head; the Editor Hat, the Copy Editor Hat, the Proofreader Hat, and the Formatting Hat.
If they are making print copies, they must wear a Deciding Hat (What company will I hire to print this? Where do I get cover art, and who can do the cover layout?), the Receipts Payable Hat (How did the final printing bill get 30% higher than the quote they gave me?), and the Signing Hat (I only ordered *** copies, so why are there so many big, heavy boxes on my doorstep?).
Think they're done? Oh, no, not yet. This part is for all authors, even those with a publishing company, whatever that company's size. Very few authors don't have to wear the following hats:
The Marketing Hat (How do I let people know about my book?) often leads to The Social Media Hat (How many times can I announce something about my book on fb, twitter, linkedin, goodreads...?), the Webmaster Hat (How do I get this shopping cart to work?), the Personal Appearance Organizing Hat (Did that bookstore ever respond about the reading I wanted to do?), the Merchant Hat (Step right up! Get your brand new red hot sf book by that upcoming new author, me!), which, of course, leads to the dreaded Bookkeeper Hat (I gave away 5 books. There's no money involved, so how do I put those in the bookkeeping records?).
I will be wearing the Merchant Hat this weekend. I have rented a table in the Dealer's Room at a Dr Who convention in Wichita KS. Tomorrow, I will be madly trying to wear both the Publicity Hat and the Organizing Hat as I try to design some way to 'decorate' that table and decide how many copies of each book to take with me. A full box of John's book, because, you know, I still have 6 full boxes to sell, 15 of my first book, 12 of the anthology I'm in (plus 6 of the companion volume for that anthology), and 12 of my latest book. Wait, will all those fit in the car with John's suitcase, my suitcase, the costume suitcase and my full make-up case?
Too many hats!