The process of making yourself a better or more knowledgable person can be called self-improvement. Doing sit-ups every night and learning to speak Mandarin might be part of your new self-improvement routine.
Anything you do in an attempt to improve yourself is self-improvement. Volunteering at a homeless shelter, going to college, learning to meditate — all of these things can lead to self-improvement. Often, self-improvement and self-help are used interchangeably. The improvement part of this word originally meant "making money with something," but by the 1640s it came to mean "the act of making better."