This is a tough one because fiction is, and has always been, very expensive and/or time-consuming to promote, and the results are never guaranteed. If there were a perfect formula for this, every major book publisher would be using it to make everything a bestseller. Instead, only a tiny percentage of fiction books go beyond their advance.
We’ve actually dedicated an entire chapter to this subject later in the book. Here’s some quick advice before you skip ahead to it, though. First, don’t openly promote your novel; people don’t seem to respond well to that. Instead, talk about the themes indirectly. For instance, let’s say the movie The Matrix never existed, and you just wrote it as a science fiction novel. Put up a web page that shows the synopsis, the first chapter, any art that is associated with it, and links to all of the major sites that sell it (e.g., Amazon, Barnes & Noble, or Kobo). Create a Facebook page for the book and a Twitter account for you as an author, and link out to your book page prominently there. Get some good Facebook ads going on a budget of $10–$20 per day to gain more page likes. Every day on your Facebook page, you would offer a paragraph or so on the nature of reality, Turing test theories, artificial intelligence, Buddhist philosophy as it relates to the plot, computer hacking, the semantics of hacker handles, news stories that deal with any of these subjects, and so on. On Twitter, you would post questions to your followers about these same subjects. You’d follow actors from science fiction shows and engage with them. You’d try to find people who talk a lot about science fiction and have a lot of followers, and try to get them to notice you (refer to Chapter 13 for more information on influencer outreach).