1.) Don't buy stupid stuff. Stupid stuff = stuff you will use once and forget about the very next day. Novelties, digital goods...
2.) Always save a portion of your income. The keyword here is SAVE. Spend time figuring out your monthly expenses and KNOW how much you'll be left with at the end of each month. That doesn't mean you get to dash to the store to buy something (see #1). Take a small percentage of your earnings and SAVE it.
3.) Buy only what you can afford. If you have a credit card for the simple fact that you can't afford to buy something and want to buy it anyway then you're looking at debt straight in the face. Instead, live off of a debit card for two months and write down all the things you gave up because you pretended to have no credit. Those "things" you wanted to buy but didn't need will still be there at the end of those two months. Oh, and so will your money.
4.) Bring your lunch to work. It'll save you so much money that I can do the math right now to tell you how much you'll save. If an average lunch costs $8 and you buy your lunch 5 days per week, you'll be spending $40 per week. That's $160 per month and $1920 per year. If you stop buying lunch every day, that $1920 can be used for Obama Care, taxes, or gas money.
5.) Create a budget. Knowing your expenses beforehand and understanding your income are two very important things. You know that you have to spend money to eat. You understand that you'll be accumulating a wad of money in your bank by the end of the month. Budgeting the "knowing" and "understanding" of this conundrum will help you balance your wallet properly by creating goals and setting spending limits. Create categories such as food, travel, and entertainment and set monthly limits for each category. Create a goal such as spending less money in a particular category during a given month and reward yourself by saving the, um – savings.
If you don't like the pen and paper route, free online services such as Mint and Wave will automatically help you manage your money like the Monopoly man.