I will try to be very concise here. I could come back and improve this post from time to time.
Baseline
This is my postulate. It is probably difficult to understand my propositions below if you don’t agree with this.
“God is dead” – Nietzsche (Gay Science). I don’t mean here that god does not exist. I acknowledge the fact that I don’t know and will never will. I acknowledge that the truth is beyond my reach (see also Gödel's incompleteness theorem). So we must accept the world as we see it as the only truth.
What is a successful life?
Nietzsche gives us a criteria to define what a good life should be: The eternal recurrence. A successful life is a life that we would be willing to live for ever.
“Live so that you may desire to live the same life again.” Friedrich Nietzsche
“What, if some day or night a demon were to steal after you into your loneliest loneliness and say to you: "This life as you now live it and have lived it, you will have to live once more and innumerable times more; and there will be nothing new in it, but every pain and every joy and every thought and sigh and everything unutterably small or great in your life will have to return to you, all in the same succession and sequence - even this spider and this moonlight between the trees, and even this moment and I myself. The eternal hourglass of existence is turned upside down again and again, and you with it, speck of dust!"” – Nietzsche (the gay science)
To live in a way that give us the desire to live this life again! This brings us the next question, how can we decide what is the life we would like to live for ever?
The Grand style
If Life as no “meaning”, No meaningful outcome, life is nothing else than sum of moments. We need to strive to make each one of them a masterpiece.
The “grand” life style is intense and harmonious. Like the perfect martial art movement.
Intense Life
What is an intense life? It is our will to push our life to an extreme. This is well define in the notion of “will of power” from Nietzsche.
[Anything which] is a living and not a dying body... will have to be an incarnate will to power, it will strive to grow, spread, seize, become predominant - not from any morality or immorality but because it is living and because life simply is will to power... Nietzsche (beyond good and evil)
The will to power describes what Nietzsche believed to be the main driving force in man; achievement, ambition, the striving to reach the highest possible position in life; these are all manifestations of the will to power.
Harmonious life
An harmonious life is one that take into account who we really are. Our strength and weakness. An happy life of course. A movement that would use our self completely (intellect, reason, feelings, fitness, emotions, …).