Ultimately, the design should be timeless, clean, masculine, and yet not threatening. Would a 20-40 year-old man definitely want to pick up a book with this cover, assuming the book cover had all the four qualities just listed? This latter question is the standard by which I will be judging entries into the contest.
You may use any color palette (except pinks and purples) and any font(s) (licensed for commercial use or in the public domain) you believe would best achieve those four characteristics.
I have included my amateur cover design to provide my initial attempt at conveying the mood I tried to set for this ebook. You may adopt this mood for your own design, but do not feel bound by it. I am not a graphic designer, so my ability to convey mood through visual art is very limited. Hence, my own design is merely a suggestion of mood, not an absolute, flawless representation of it.
For more about the mood I'm looking for, a piece of music probably does better than my cover: Listen to "Last Man Standing," by Hybrid. It's on YouTube (https://www.youtube.com/watch?v=4SqUYOKZgpU).
This ebook is edgy, and some parts of it are gritty and dark, but it ends on a very inspirational, uplifting note. The advice is "tough-love" kind of advice -- it is filled with hard-won lessons and uncompromising language -- but behind it all is human warmth and the genuine desire to help men become stronger, better, healthier, wiser versions of themselves. I would very much like the cover to reflect some of that warmth -- but to reflect it in a subtle way. In the contest, if there is a tie between covers that about equally match in their characteristics of being timeless, clean, masculine, and non-threatening, I will break the tie based on how well the cover conveys a subtle human warmth. I was not able to encode that warmth into my sample cover -- the light-colored geometrical shapes just didn't quite do it.