First layer, health. This includes all the known physical methods to boost health, such as good diet, regular exercises, low stress, access to quality medical treatments when demanded. Almost everything discussed in this forum falls into this category.
Second layer, happiness. This receives less attention but is probably more important, for how can a person be unhappy while at the same time be healthy? Fortunately, everyone can improve happiness by employing some practical methods. Play pickle ball. Take a walk. Dress well. Learn to embrace adversity and challenges as they come, learn to find joy in otherwise boring duties, learn to slow down and enjoy everything that life has to offer. It is even possible to guauge happiness by monitoring how much dopamine is secreted.
But the ultimate happiness comes from the third layer, that is, tranquility. Tranquility is the deep ocean below waves of happiness. While happiness is acquired by doing something, tranquility is acquired by doing nothing. It is the knowledge, or rather, the assurance that every moment of life, now or later, is complete, beautiful and empty by itself, requiring no any external conditions. It is complete, because nothing else needs to be accomplished or to happen in order to justify this moment as a happy one. It is empty, because tranquility is simply the absence of noise, the synonym of emptiness.