The best advice I can come up with is this: Keep your living expenses LOW. The smaller you live (materially-speaking), the bigger you can live (creatively-speaking). This way the stakes aren’t so high…you aren’t demanding of your passion that it keeps you living a rich life. Then you can stretch and grow with the most possible freedom. This was my strategy in my 20’s, and it’s the reason I worked really hard to avoid all debts, and to keep my lifestyle really manageable. If I’d been saddled with a big life, I don’t think I ever could have found my way forward to the freedom I have now.
Some practical advice from Elizabeth Gilbert in response to the question: What is your best advice for people who want to turn their passion into a career?