It is important to understand that gambling is a form of entertainment and not a way to make money.
That's the first mistake most people are always making, they are always taking gambling as source of making money, which is wrong if I ask most people that I know why they gamble, they will endup telling me is because they are in need of money, if you are gambling mainly for money, then you will end up being addicted and you will keep on losing money, because you will always chase your lose.
Set a budget: It is important to decide how much money you are willing to spend on gambling in advance and stick to that budget. This can help you avoid overspending or getting carried away.
If you are not addicted to gambling, then you can stick to budget, but it's always difficult for addicted gamblers to stick to budget, the only thing that do stop most addicted gamblers from gambling is that if they already exhausted all the money they are having with them, that's when they will start coming back to their right senses.
Stay sober: Alcohol can impair your judgment and make it more likely that you will make poor decisions while gambling. It is important to stay sober while gambling to help ensure that you are making decisions based on clear thinking.
I don't know why you should drink before you gamble, if you are drunk and you want to gamble, then you are just planning to waste your money, because you are not really in your right senses at that moment, if you want to gamble, then you should avoid alcohol.