From my limited view and understanding, if you can find a promoter to pay you to fight then you just have to get your pro license, medical exam, and all of that. Then you can get paid to fight. Depending on how your promoter sees you, you will either be the "home towne fighter" or the "opponent". Could be different depending on what side of the pond you live on. I have talked with a couple of club fighters (both opponent fighters) and both had extremely limited amatuer experience. Some of the other folks here can give you a better idea, but this is from my limited knowledge.