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I wrote a book about my feelings about ptsd. I would like to share my book. It is fiction. But the feelings are real to me. What should I do?
Your 2 baseline options are to either publish, or self-publish (with, or without, the hope of being picked up for professional publication later).
There are whole books & periodicals dedicated to helping writers understand the world of publishing, and getting their work published; and a tremendous number of articles on self-publishing, weighing pros and cons of different platforms, media, etc..
Step One : I would research my options, and decide which track I’d like to take (or at least try first).
I started writing for publication a little over 30 years ago, and even waaaaaay back then very very few publishing houses, or editors, accepted “unsolicited manuscripts”. Which means either finding an agent, or looking for opportunities to add to someone’s “slush pile” (IE open solicitation, rather than directed; like anthologies, magazine articles, etc.), until you either pick up an agent, an editor, or an open invitation…. Or all 3. I haven’t written for publication in awhile, so when I say I would research? That’s literally what I would do. Find out what’s going on in the industry, in this moment, and decide which directions I would want to work towards.