I think the safest method to gamble a bit safe and also not risks too much is by pokerring because you can than really push the luck to a minimum with a good strategy of course.
Poker is still based on luck, you can have luck with the cards or not. Even if you are total king of poker experts.
Examples of some amazing poker luck:
https://www.youtube.com/watch?v=2xqaxWQO79g and
https://www.youtube.com/watch?v=sKsV6oqZW38 situation like this can't be predicted.