I would use the free money to gamble for fun and try it out. If I feel comfortable, I will put my own money there.
Well that is what I'm doing too if there are a lot of sites that does offer free credits for gambling but of course you are not going to win real money then that is going to be the best way to enjoy it. For me, that is going to be enough for me if I only want to have fun with gambling because that is only the way to get safe with gambling for fun.