The safetiest that i know is to use the faucet bonus don't spend your bitcoin from your wallet just use the faucet bonus and make some profit if you are not lucky to get large amount.. its better to stop so that you can control your self for being greed..
think there is a safe way to gamble, you can start doing faucets and only use those satoshi to gamble. That way it won't hurt you as much as losing actual bitcoins or real money that you earned.