Pick one game that you wouldn't mind playing for hours on end. Devote all of your time into getting good at that game. Become a dictionary for every mechanic the game has. Get good enough to have a decent online footprint, quit your day job, and stream your daily practice for donations. If you get big enough you might get sppnsored. Take all of your skill to a tournament and play for a cash prize. Win or lose, go back to streaming until the next tournament.