Seems the same as learning anything really, well thats been my experience anyway. Once you get to a certain level at trading you can earn cash, or carry a learned occupation with a reasonable degree of proficiency, does not mean that you will end or end up a consistant full time trader but you'll be good enough to give it a go and it should not cost you the earth.
Aside from actually doing it, how would you find out if your good enough (intra day day trading)