I am 32 and still working on it. I made my first attempt when I was 16 or 17, and it was laughably bad. I came from a lower income family and really didn't know much of anything about business or how money worked. The upside is I had become great at saving since money was always so scarce for me.

I have tried several things since then, but mainly I have been learning. I had the misfortune of getting started right at the end of the "dot com bubble" and there was so much scammy junk out around then. I knew nothing about busniness, and most of what I could find online back then was about how the old rules didn't apply anymore in this new whizbang age of information.

First, I would say make sure you know some basic accounting, since that really is the language of business, and then some basic economics, since that is sort of the bigger theory. Don't be afraid to read textbooks. Business economics and managerial economics are some titles/areas to keep your eyes open for. Once you have a sense of how things work learn everything you can about market research. Most of my ideas in the last 6 years or so never got off the ground, but that means I didn't lose my shirt because I had figured out how to identify bad ideas. So I consider them learning successes. Always listen to the market, it is your boss.

I suppose to get closer to what you are asking, I never really stopped pursuing my dream, I just learned how to pivot and never gave up. Time management is always going to be the core skill though, so take this opportunity to learn it while you don't have the big risks of "adult" life if you screw it up. And never be afraid to fail, but always choose your battles. And always have a plan. I guess that is enough for my ramble. Best of luck!