The best way is to think of money in the long term.
For example, instead of buying a junker of a car. Buy something a little more expensive, like a car just off lease, that is more reliable and requires less repairs and maintenance. In the long run, it costs you less to operate per year then a gas guzzling SUV you bought from a neighbor that breaks down all the time.
You buy a computer, buy something with more reliable parts and keep it working longer instead of replacing it every two years.
When borrowing money, shop around. Get the best deal you can. When paying back money, pay back the highest interest loans first. For example, lets say you have $1000 in credit cards at 14% interest and $500 at 3% interest in your line of credit. If you pay off the credit cards first, you save more money. Even if you only have $500 in the line of credit, if you pay off the credit first you pay less interest. Work it out on paper if you need proof.
... etc.
Sources: I'm in school for Business Finance, I can get you some links for reading material if you want.