Striving for excellence.
Communicating your truth: what makes you happy or sad? What do you find exciting or frustrating?
A team. A support system. You need one, create one. Otherwise you end up doing drugs.
Marketing, which is another form of communication.
Selling, which is another form of communication.
Getting your things to people who want them.
And there are all the human aspects. Keep the human aspects in mind, because you want production over time, not a burst of production in your 20s and then nothing.