If there's one thing I've learned after self-publishing three books, it's this: they don't call it the "vanity press" for nothing. Just web-search "self publishing" and you'll see an endless list of gurus, marketers, artists, author services and publishers who all promise to make your creation a success, for a price. Sometimes, the price is pretty steep and the results aren't guaranteed or even relevant.
Once you decide to self-publish your work, you have to accept Hard Reality #1: You will probably never become rich and famous. Yes, there are exceptions but mostly, no. This doesn't necessarily mean you and your work are of lesser value, or that you won't develop a fan base. It does mean you have to work harder to get the word out that your book is worth someone's time. It's hard enough to get people to read anything, let alone an unknown author.
This leads to Hard Reality #2: You are your own agent, publicist and PR flack. The extent to which you achieve success through self-promotion is directly tied to your use of free venues such as social media, email, YouTube and word-of-mouth, and paid venues such as social media ads, Google ads, local newspaper and print ads. I've used all of them and I still sold only about 60 copies of my first novel in a year's time, and a couple dozen of my second novel in the two months it's been available. But you gotta keep doing it.
Finally, Hard Reality #3: The self-publishing industry wants your money, will take it in a heartbeat and offers NO guarantees of results. Promotions that promise a ton of Amazon reviews by putting your book before 30,000 Twitter fans are a joke. Websites geared towards self-published authors sell ads on their own sites to their own members. There are promotions and social media campaigns supposedly aimed at people predisposed to reading your work, but offer no accountability of the effectiveness of these products. You are left to assess the results on your own, based on things like your website visitors and book sales.
My bottom line is, don't put yourself in the poorhouse by jumping at great-sounding quick fixes for book promotions. Don't get super caught-up in mutual admiration societies. Keep writing, guard it against theft and enlist one or two trusted individuals to bounce things off of. Use your social media accounts. Get yourself a Mailchimp account--it's free for up to 2,000 subscribers--and build an email list. Strategically give away some books to key people who will make a difference by spreading the word in their own way. If you have any skills in graphic design, photography or video, use them all.
There's a lot you can do yourself, or with a little help from your friends, before you start shelling out endless dollars for promotional gimmicks with mixed or no results.