Since I’ve gone down the self-publishing road, the best advice I can give is to listen to everything that’s already out there. I made just about every mistake when I started out that everyone tells you not to do when you self-publish. It didn’t have to happen that way; it was my own fault. For example, if you have to, pay a copy editor to clean up your manuscript. If you aren’t a designer, don’t attempt your own book cover. Sure, I went back and fixed my early mistakes, but sometimes the damage is done before you can correct it.