James Nunn: Graphic artist
Here are three tips that he mentions:
1. Be a reader
"Being a reader helps enrmously in cover graphics. Often I come up with concepts that I could never have thought of without reading the book."
2. Bring energy and imagination
"That way you can give the publisher what they've asked for and what they didn't know that they wanted until they saw it."
3. Keep it simple
"Among all the work you show make sure there are some very simple striking images with just one idea. The best book covers just have one idea that hits you right between the eyes."
Jack Noel: Book Designer
"Do what you can to learn the computer programs (InDesign and Photoshop, mainly) and create a portfolio - fill it with whatever you want - redesigned book covers, logos for friends, posters for bands that don't exist. To be a designer you need a little bit of skill and a lot of enthusiasm and a portfolio of self-initiated projects is a good way to show both."
Kirk DouPonce: Book cover designer
"As much as I would like to say that book covers are purely art, they're not, they're marketing. The mission of the cover is essentially an advertisement to sell the book. But they're art as well. They literally give the book a face."
"Designers and illustrators need to develop a thicker skin. Having said that, it's difficult to not be emotionally attached to your work. Since I generally have to create three comps, I'll try to create at least one to make me happy and the rest to make the client happy."