Publishing is in a state of flux. Every variation of publishing is possible today, from throwing it over the transom to an agent who handles it all, to doing every single step yourself.
In between are various levels of self-publishing, defined to some extent by the balance of responsibility and risk shared by the publisher and the author. Understanding those differences is vital to your success. When I was asked the question in the title the first part of the answer was getting our definitions straight.
First, read Dave Bricker’s stupendous article on the difference between self-publishing and vanity publishing.
Done? Good. Let’s talk about self-publishing, and ignore vanity publishing entirely.
A “self-publishing company” is going to be something like a book shepherd: someone who guides you through the process of doing it yourself. (This is what I do, including all the steps below.)
They might help you get the book written, with mentoring/coaching, guidance and developmental and general nudginess. You might work with them because you need this, and they’re good at it.
They might offer other kinds of editing, proofreading, etc. You might work with them because you really need help with sentence structure, spelling, etc. This is not uncommon among authors. Honest it’s not.
They might offer cover design. Unless you’re an artist, you want help.
They might offer marketing advice. If you’d like to spread your message, you might want help. (If you’re writing a book to make money, may I recommend real estate? The market will be booming again, beginning in late 2014; just enough time to get your license and get established enough to ride the gravy train.)
They might do your marketing for you. (I don’t. I only work with authors who are breathing fire at the chance to tell others about their work.) You might work with them because you don’t like selling and will accept a significantly reduced profit margin.
Here’s what I’d look for: someone with an established track record of producing quality work. The books produced have quality covers, are well edited, and generally look professional.
Of course, I just look in a mirror for most of it, then use CreateSpace for my print on demand needs (though Lightning Source is also excellent, just more expensive. LuLu also excellent, but even more expensive than Lightning Source.)
If you think a book shepherd might be helpful, let’s talk.