There are two options: You can send your manuscript to an agent or choose to self-publish. Keep in mind that when you send your work to a traditional publisher, it can take you a long time for your work to be recognized. More often than not, your work gets rejected. If you don’t have the patience, you may end up getting frustrated.
When you self-publish, you pay to get your book out. This can be a trade-off, but the gains may be more than you expect. Many authors nowadays turn to self-publishing for many good reasons - they have complete creative control of their book / retain ownership rights of their work / their book never runs out of print / use it to jumpstart their publishing career, etc. Most importantly, with self-publishing, you only have yourself to convince.
Self-publishing is also a smarter option especially that you are planning to publish a book on a specific niche, because you can actually cater to your target readers. You also get to control the number of books you want to have printed. Usually, your POD publisher only prints your book depending on demand. This way, you wont end up with a garage full of unsold books.
In regards to marketing, several self-publishing companies offer marketing services to help get your book out.
Whatever publishing route you choose, make sure that you understand how publishing really works. Publishing is never easy, so you have to know how to play the field, at the very least.
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