To be honest, I don't know anything about design. However, I sometimes would like to have decent covers for my eBooks collection and I don't want to spend extra bucks on that. So if you're just like me, use online tools.

Websites like Canva, Picmonkey, and Designbold offer a huge number of eBook templates with various design styles and elements. The best thing is that they are all free and you can quickly whip out an eBook cover in just 10 minutes!