Amazon will do its part to publicize your book by giving it a page of its own and displaying its cover in a variety of places on other pages: New Books This Month, Bargains under $3.99, Best-Sellers, Top-Rated, "People who bought this book also bought . . . . ," and
"You might like . . . " But you have to do your part by creating a cover that meets their standards, AND one that attracts curious readers. Here are a few tips on how to do that.
The general rules for formatting your cover are included in the free Kindle publishing guide, which you can download at: <http://www.amazon.com/dp/B00822K3Z0>. Be sure you get the guide and read it carefully. It will save you a lot of grief later on.
Remember that on a computer screen, the image of your cover may only be an inch high, and you want it to be legible. People won't buy a book if they can't read the title. Use 40- to 60-point font for both your name and your title.
Usually your title is the most important element. When you hit it big and have a huge fan base that will buy anything you write, then you emphasize your name.
If you write a series, or if your books all come from the same period and setting, the covers should look similar, so that readers begin to recognize the style.
To further that effort, put the title and your author name in approximately the same spot on every cover. Also, use the same font for titles in a series.
Simplify your cover design, so that the most important element stands out.
Wherever possible, use 3-D covers like the ones above. Turning the image a bit, so that it looks like a real book rather than a flat rectange, makes a huge difference in spur-of-the-moment purchases. You can Photoshop the images yourself, or find any number of artists who will do it for you. My images above cost me $5.00 apiece. Amazon will not use a 3-D image as their primary one, but if you look closely at your book's Amazon page, you'll see that it says, right under the picture,"Share your own customer images."
You can add your 3-D image there, and anyone who goes to the page can click on the alternate image and see it as a "real book."
Remember this Tip of the Day: Covers Sell Books!