How do you know if the gambling site is a scam or not? how you trust a gambling site for you credit card and know its not a scam?

Quitting gambling is hard, the 1st, thing you want to do is take a short break try 3 days break then 1 week then 2 weeks. 2nd, you can do is find an activity to distract your self like playing sports, or just spend you money wisely. 3rd, ask for help, don't be ashamed if your willing to quit.

In my opinion I would say there is no strategy, it all depends in your luck. but if you are really good at playing and like poker and etc.. and enhance your skills in playing. that would be a strategy to win. 

In gambling to control your self from betting more and making your self broke, I would suggest you to have a limit. For example, before you play, set yourself a limit for just "lets say $1000" then or get $1000 in your wallet and give it to your wife/friend so you wont be tempted to play more. if you win more its your choice to play more but if your $1000 is gone you'll just leave because you have no money on you left. 

For me If I already get a double, I would take my money and not risk to spend it all again and lose all of it, but it really depends on the person if he/she wants to spend all of it again he/she might get it double again or lose it all, it all depends your luck  

You can stop gambling by making yourself busy on other stuffs than gambling. Spend wisely on your money. You can divert yourself by just playing sports just keep out from internet or casinos. 

Yes, Investing online is risky but so as gambling. If you properly look for a legit investment which you know that your going to earn money in the future,  is much more reasonable than betting on your luck. In gambling if you have no luck you're just wasting your money and making the gambling companies more richer.