For me, I would say you start by setting up a budget on how much you are willing to spend and don't go beyond the figures. Furthermore, you have to understand the probability of winning and losing -- never get too carried away by the odds you see there and don't allow emotions to controls you keep your mind calm.
This is really a very good approach of gambling if all the addicted gamblers can adopt it, it will help them reduce addiction and even if any other gambler both new and old adopt such method, they won't face the risk of addiction. Anytime I go gambling, I always allocate the money I can afford to lose, after which, I don't make any other deposit.