In the field of cartooning there's a famous character designer named Stephen Silver. On his art blog he had a list of tips to be more creative in art, business, etc. (
here)
He gives a couple pieces of advice that retain very well to being a freelance artist... they hit very well from what I've experienced in my work.
"Keep your day job." They don't call them starving artists for nothing. There's good times and bad times... From my freelance experience, it's been a nice little bit of extra cash every once and a while... Like, I charge $30 for commission, and I get one every couple months, maybe. If you want to reply on it as a job, especially if you're just starting out, its not worth it. On this list he also adds "Selling out is harder than it looks." and "Being poor sucks."
Another very good bit he brings up, "The most important thing a creative person can learn professionally is where to draw the red line that separates what you are willing to do, and what you are not."
and, "Beware of turning hobbies into jobs."
