Set a budget for a certain length of time and stick to it. If possible, try not get it down to zero. Once you run out of money, you can't deposit more.

For example if you set a weekly budget and lost all that, you don't replenish it until the next week. The good thing about setting a fixed budget for a regular interval is you can track if you are earning anything.

The habit that you have to avoid when gambling is:

Don't make a lot of bet while gambling

This is the reason why people lose. When you make a lot of bets, you decrease your probability of winning in total profits.

Besides keeping track the bet sizes would matter more. When winning or losing people tend to make bigger bets what carries more risk.  Keeping track wont help to win more or less.

It didnt decrease your chance either  . you will still loose even if you are only betting small but this is better at all times . whenever i play gambling i tend to bet lower because i want to spend more time in that game  .  

some gamblers would be doing the other way around because they find it boring to bet less and  it will only take time to achieve their waggering requirements

My additions:

1. Not mentally preparing - don't gamble when you are depressed or angry, it'll just make it worse if you lose and it's going to affect your play.

2. Not making a budget and sticking to it - if you just keep on pulling money out, you could soon find yourself short of cash for other stuff. You could end up dipping for money reserved for utilities, etc.

Statements like this are only made by gamblers that are not willing to learn the required skills in each game. If we hear stories of gamblers winning million dollars from gambling, what stops us from believing we can also achieve this? I read something on the news last week about a guy that won over 50BTC from one of the gambling sites and according to the news, he had never won a dime before that time. Sometimes patience and a heart that is opened to learning is all we need to succeed in the game.

The percentage gambling investors get is nothing compared to what they make from playing directly on the site. So why invest when you can as well play and even make more profit? Just cancel fear, go for more knowledge and be determined to make money from the game and you will surely make it.