You will save a ton of time and 2 tons of money if you start by getting a job in a cabinet shop for about 6 months. Then get a job working for a small custom woodworker for about a year. Then try your luck on your own.
This sounds strange from me because I am one for just jumping in to it. And, I once did. For the first year or so, I lost my rear end, big time. Was way too much in debt. I had read all of the woodworking books on the market. They are great for working for fun. When it comes to making a living, they are total and unadulterated B.S.
If you work even for a small cabinet shop, you will be exposed to limited production methods, which on your own, you will be exposed to none. Then if you work for a custom woodworker, you will find that he was probably an art major and at one time or another he too worked for a cabinet shop. With him you will also learn limited production techniques and maybe a design idea or two.
When I was about to pack it all in, I hired some people for a small run of boxes. The way they set up and did it, you will not find in any books. Then I hired a custom woodworker with a great cabinet shop background. I learned more from him than imaginable. It doesnt take long to learn production techniques, many of which are just simple jig making. You will learn that sometimes you can construct something out of mahogany much faster and more profitably than trying to stain oak to look like mahogany.
Along with their woodworking skills, you will also pick up resources for hardware and misc. These are the kinds of places that if you are not in the business, you will never discover them on your own. You can spend 3 hours making a Queen Ann leg or you can buy it for $45. Most businesses today cant survive on less than about $45 to $60/Hr. Keep in mind that if you build and make $45/Hr., that is how much you are making when you are working. You will find that you will spend a lot of time driving around giving estimates, pricing and ordering supplies, designing pieces and record keeping. These are the hours you dont get paid for.
Like I said, I am normally a 'jump in with both feet' kinda guy but I guarantee that if you were piddling in woodworking for as little as 15 years, you dont know anything about woodworking for profit. "For profit" are the key words. If you want to work for $10/hour, you will have all of the business you can handle. Raise your prices to $11/hour and you will lose all of the customers that bragged on you. Now you will have to build a new customer base.
I hope my litle rant dont completely discourage you, but it should serve as food for though.