For me, responsible gambling means gambling with money you can afford to lose, not money needed for daily needs or other obligations. This means having a clear limit on how much money you can afford to gamble and not exceeding that limit.
I believe that responsible gambling also means having clear priorities regarding other needs and obligations, such as paying bills, saving for the future, and supporting your family. Gambling should be a form of entertainment that can be enjoyed without sacrificing other basic needs.