No matter what you learn from others, at some point you just have to take the giant leap and do it. More specifically offer a good service and believe enough in yourself to charge for it.
Start doing and start charging. Sounds simple right?
I haven't ever had the desire to do it or I would have done it years ago. I find plenty of satisfaction doing it as a hobby, but I know I could have done it.
Money in performance music probably isn't as profitable as making money recording for other acts. The education starts as soon as you start. During the education you can't quit. If you offer a good service someone is eventually going to pay you for it. Don't be a Mr. Nice guy...don't make too many exceptions or you'll never make any money.
Get paid up front and have them sign a contract. Make sure they know what you will do for the fee and what costs extra. Just do it.