Many readers judge books with great covers. Covers that appeals to their mind's eye. Covers that excites them enough to pick up the book and to turn the pages.
One benefit to self-publishing is that the author has control over choosing a cover, But just because he/she has control over and/or input doesn't mean you know how to choose a dynamic cover.
Here are some examples of what you can do in choosing a cover:
(1) Get on your computer and search for designers. Look at their portfolios and view their client lists. Pick one who will allow you some control and rely on his/her expertise. Do your search early. It may or may not take you long to find the right designer.
(2). Go to Amazon.com and take a look at which books are selling the most, or visit a Barnes and Noble and notice which covers evoke emotional responses from buyers. Ask them, "If you don't mind, tell me why you like the cover of the book you are holding."
(3) Get feedback from your readers who purchased your other books.
(4) Start your design after writing your first draft. Don't select a cover that is set in one city or state when your book is set in another. Give your designer all of the details about your book. You need to make the spine look real or you may end up with a distorted look. It should represent what's inside the book and is in no way misleading. Make sure you have the right size and font. If covers are too dark, when it gets older, it'll turn into looking like mud once it's shrunk. Too many small details won't be noticed. A cover with fewer details is better.
(6). You need to lure your readers in and give them a taste of what is to come with your other books. No matter what publishing path you pursue, covers play an important role in your success. Make sure your covers are the best they can be.