When I started I read all the books that were available and got pretty educated, but still did nothing. Then I did a course and got the confidence to actually do something. I don't think it was the specific course, but I just needed something to give me that lift to make the first leap.
I didn't look back, and kept on building my portfolio. I'm no Trump, but no slouch either. And it's all because of doing a class.
Of course, you have to take that with a grain of salt because I'm teaching now too!!
It's all very well reading books, but to see and/or hear someone who's "actually done it" (or say they have ) can be the catalyst to think "I can do this, too!!"