Invest wisely. Research stocks and know the amount of money you are willing to lose. High return equals high risk. Stay diversified and you should not be disappointed.
Pay yourself first. One simple word, save. Before you pay rent, bills and the like, pay yourself that is why you work. Take it out of the money been before it gets passed around.
Use cash. Using cash not only gives you bargaining power, but it also brings spending to a more tactile experience. It is much easier to impulse buy with a card, but counting out the cash is a bit harder to do.