I'm a professional as well as TJ, my site is
Dealt to Hero - Tips from a professional online poker player.
You're actually asking the wrong question, because if you are a winning enough player then you'll already have the money. So by asking this question, I can assume you're not a winning player. TJ Cookier's post explains how a lot of pros do it (even myself!): pretty soon you're winning so much that you don't need your "real job" anymore.
So to go pro, the best thing to do is treat poker like a night job, and when that night job starts making more money than your day job for many months in a row, that's when you go pro.
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