Describing what matters starts with what doesn't matter. It doesn't matter how much money you make or what kind of house you live in. It doesn't matter what car you drive or what city you live in. It doesn't matter what your skin color is or what gender you were blessed with.
What truly matters in the end is how you live your life, and this doesn't mean leaving a legacy after your gone, though that may be important. If we give of ourselves, rejecting selfishness, we are on the right track to what really matters.