Built your mind. Reading, Learning, Journaling. Journaling [ˈdʒɜːrnəlɪŋ] is the act of regularly writing in a journal or diary, often for personal reflection or record-keeping.
2:
Build your body. Gym, running, nutrition.
3:
Build your money. Business, skill development, investing.
Most of the good thing in your life are downstream of those 3 things. Anything more than them is a bonus, and anything less is self-destructive.