We publishing Browncoats (Firefly reference; allusion to Independents there) are responsible for all our own marketing. Nowhere is this more crucial than in the book description we write for the various e-marketplaces.
I’m assuming you’re writing fiction. For us, the best option is to use our elevator spiel. If you don’t know what that is, ask yourself how you can summarize your book to a perfect stranger in the two minutes required to travel by elevator in such a way that he wants to buy your book. They’re short, to the point, and juicy.
This works, you crazy hep cats! I just released my book A Path of Stones today. That means, I activated the links on my website. The books have been available on Amazon, Lulu, and the Apple ibookstore for a week now. I already sold eleven ebooks in that week! It can only be because I wrote a humdinger of a description.
Here is the one for A Path of Stones:
Newly initiated wizardess Aura Lockhaven has a strange power within her that enables her to perform miracles. The path of the enchantress offers her hope to harness that power before it kills her. To discover more, she visits the Valley of the Mystic Moon, the home of the Order of Enchanters. The Order is not so enchanting, however. A monster wants Aura’s soul. A vengeful ghost wants her head. A renegade lawman wants both. A mad noblewoman believes Aura is the fulfillment of a prophecy. Finally, there is something about her mother’s maiden name that attracts the wrong kind of attention. Aura may not survive walking A Path of Stones.
My main goals in writing it that way was to convey what the story was about, in suspenseful terms, and to let the reader know this is not another story about a group of mismatched characters walking 1,000 miles to save the world from an evil villain. I must have achieved my goals.
Writing for Bowker’s Self Published Writer newsletter, Penny C. Sansevieri goes into much more detail than I can. I’ll simply link you to her article and tell you to read away: How Great Book Descriptions Can Help Sell More Books.