So you go in search of promotion and marketing tips. Maybe you Google "how to sell your self-published book" or "how do I sell my self-published book." You read a lot of articles and a lot of lists on how to do it. And you implement some of those strategies. Maybe you start doing giveaways, or you get on a blog hop, or you swap reviews with a fellow author, or you get a high-profile review blog to give you a favorable (three stars or more) review. Or maybe you go a different route and start acting like a jerk because controversy gets you attention. Maybe you decide to be obnoxious and tweet at your followers to buy your book or GTFO. Maybe you flood Amazon and MobileRead forums with your book plug. Maybe you direct message anyone on Twitter who seems even remotely interested in reading. Whatever your strategy, maybe you get a few more sales, maybe you don't. Maybe you're right back where you started wondering what's wrong.
1. Write a good story.
Seriously, this is the most basic thing. You want to sell books? Write books worth reading. People won't tell their friends to read a book they didn't enjoy, and word-of-mouth is your very best marketing tool.
2. Get the formatting right.
Use the Smashwords Style Guide (even if you're not publishing through Smashwords). Use Calibre. Download the apps for all the formats you plan to offer your book in and look at your book. If you can't get the formatting right on your own, pay someone else to do it.
3. Make it readily available.
Give people options. People love options. They want to read your book on their smartphones or on their computers, their electronic readers or their tablets. They want to buy your book in print or print it out themselves at home. Let them.
4. Identify your target audience and market to them.
As narrowly as possible, identify your target audience. Think of it as a characterization exercise if you have to. Imagine your ideal reader, everything from her physical appearance to the car she drives to the emotional baggage she carries to what she does in her free time, and figure out how to reach her. Then do it.
1. Expect a majority of your sales to come from fellow authors.
Tweeting and blogging about writing is going to attract writers. These people are not your target audience. They are your support network and your competition and there are probably a few new friends among them. But they're not likely to become die-hard fans.
2. Be a jerk.
Just don't. Controversy might get you some attention at first, but people aren't going to remember your work unless it's spectacular. And if you have to resort to being a jerk, your work sucks. So you're just going to end up looking like a jerk who can't write.
3. Be ungrateful.
Especially in the beginning and even later. (Nothing makes me want to read an author less than when they seem to assume everyone should read and love their work.) Every sale you make is a sale you didn't have before. Every review you get is proof that someone cared enough--and it doesn't matter if it's a one-star review or a five-star review--about your work to tell others about it. People don't owe you anything just because you typed a few words up on a computer screen.
4. Think you're better than everyone else.
If you were, you wouldn't be self-publishing and struggling. Just accept right now that you're one of a million, not one in a million, and work on getting better.
Expect to spend two years building your "brand" before you see any sort of significant result. To be safe, I'd say don't expect success before year five. Don't give up.