I've heard it said that every business, to stay in business, must take inventory. A business owner must know what they have and what they don't to establish what their needs are, and how to meet them. Think of your finances as a business, because it is.
How do you know what you have, what you spend, what you owe, etc., if you don't take a regular inventory. Many of us know what we owe and what we earn, and we chip away at our debt. But the question of "What can I afford?" is often met with vague ambivalence.
It is so important to truly know where your money is going every month. So I am proposing a challenge for you. For 30 days, keep every single reciept for every item you purchase. Keep an envelope in your car, or in your pocketbook, or even at home, and place every single receipt in that envelope for 30 days. Keep a copy of every bill you pay during that time as well; car payment, rent or mortgage, gas bill, credit cards, etc.
At the end of the month, seperate out any items you paid for with a credit card, and evaluate those seperately. Ask yourself, "Am I paying interest on things I don't need to?" If you are paying interest on food, clothing, movies, eating out, or other depreciating items, you are wasting money.
Secondly, look at all of your receipts, and evaluate where all of the money goes. Set up a ledger, and put the cost of each item in a section. Food, fuel, clothing, hair products, energy drinks, cigarettes, etc. Evaluate where your money goes, so you can determine if this is how YOU want to spend your money.
If you don't write something down, you are only cheating yourself. This is a one time thing, and if you like it, and learn from it, do it more often. Perhaps every six months. The only hard-and-fast rule to this challenge is that you be honest with yourself. Take an inventory, see what it shows you, and save the money!