Up until I was about 22 I worked for various companies. When I was 22 I moved away from home and got a job with a small office and carpet cleaning company. I remember meeting one of the owners at a McDonalds. He had all the equipment needed for cleaning the restaurant overnight, floors (both eating areas and kitchen), bathrooms, windows (squeegeed inside and out every day, 7 days a week. The first night took me 9 hours. The next couple of nights 7 hours each. Every day I would cut my time down as well as figure out better and faster ways to do the cleaning. I also assisted them cleaning carpeting. I paid close attention to what I was doing. Eventually they had me training others to clean new accounts. I also filled in for when others were absentee. Within a short time I was getting my own jobs and eventually struck out on my own. After 2 years I ended up moving back to my parents' house (winter of 1979 in Chicago! I was in Chicago when the snow started. Turned on the radio to hear what traffic would be like going back to Naperville, IL - heard that a semi had jacknifed and was blocking all lanes going where I wanted to go. I decided to go to Northbrook where my parents lived. Got used to being back home and not living with several other bachelors who were in my church.)
After deciding to move back home I started my own cleaning company based on what I had learned first hand and from what I had learned from Jack Roth at Able Supply, a very good janitorial supply house in Skokie.
Had my own office cleaning (and related jobs) business for almost 20 years. I also did my share of house painting, both in and out. After almost 20 years of this (including working late at night or getting up in the wee hours of the morning to clean offices) I stopped and went to work for a real estate manager I cleaned for. She was specializing in foreclosed properties. I swore I would never paint again. I ended up doing some painting on foreclosed properties, but not full time. When the realtor I worked for went out of business I had to figure out how to make a buck. I decided to go back to painting. Shortly after that I joined this forum and have enjoyed all the advice I have read since then.
You sound like you have a big jump on me as far as painting. How have the contractor(s) you have worked for liked your painting? What kind of feedback have you gotten from those you have painted for? If you are hearing good and good you might do what I and many others have done once they have gained the skills to do a job right and realize that can go off and work for themselves. As far as proving yourself on this forum, I would suggest that only you can judge whether you think you and your skills are good enough to find work directly for your customers and not just working for a contractor. I hope some of this helps. You are in the right place for asking advice, something I wasn't in back in the old days. Good luck!
futtyos