The main purpose of your book cover is to get the right person — the kind of person who is most likely to buy your book — to notice your book in the first place. In your local bookstore, the cover should be readable from about 10 feet away. Likewise, the cover of an e-book has to stand out on the screen of an e-tailer storefront. View my cover portfolio.
Designing for e-books requires many of the same skills as designing for print. In most cases the print design will be used, and few changes beyond cropping out the spine and back cover are required.
One major difference between e-books and print involves color: Computer screens use the RGB color model while print color uses the CMYK color model. The print designer has to check the printed color for accuracy. Some colors that appear on screen cannot be printed.
Covers are almost always printed in process color (four inks — cyan, magenta, yellow, and black — blended together on the printed page to produce a range of colors). Not every visible color can be represented in ink. Sometimes additional spot colors (inks in pre-blended colors) or varnishes are added to the usual four process inks. A book cover may also be foiled, embossed, or die cut.
Covers are laid out in a flat, a single sheet of paper for front, spine, and back. The paper is larger than the actual cover to allow room for the bleed, where the design extends outside the book’s final dimensions. The bleed will be trimmed later.
The cover designer needs to know the final trim size of the book, the number of pages, and the paper to be used. With these last two details, the designer can calculate the spine width. Many printers also provide an online spine-width calculator.