At some point, we all spend a little more than we'd planned, save less than we wanted and have made a horrible financial decision or two. That's just life. But financial mistakes -- like most mistakes in life -- can generally be avoided with forethought, planning and self-discipline. And of course, it's best to know what kinds of behavior to avoid at all costs.

Here are some of the most common financial mistakes people make. If you can learn to steer clear of these, you'll be well on your way to a bright financial future.

Money Mistake #1: Not Paying Attention to Balances
Do you know how much money is in your checking account right now? When the money for your rent or mortgage will be withdrawn? How much you'll need for groceries, gas and other expenses? If you answered "no" to any of these simple questions about your checking account balance, you've stumbled onto a major money mistake -- and an inexcusable one at that.

How to Fix It: One of the best ways to save money is to find out how you're spending it. If you don't know how much money you have, you can't even begin to spend it wisely -- or ensure that it doesn't run out before your next paycheck comes in.

These days, virtually every bank and credit union offers online banking, which you can access anywhere, anytime. Get into the habit of checking your balance regularly, and choose some accounting software, an app or an online service such as Mint.com to help you sort out how much you're spending and what you're buying every month.

Keep Reading: 4 Reasons Automating Your Finances Can Be a Really Bad Idea

Money Mistake #2: Buying Little Things
Few people buy a new car or a big screen TV on a whim, which is why it's actually the little expenses that often do the most damage to a budget. Expenses like restaurant meals, coffee, entertainment and other relatively inexpensive items tend to be purchased without a second thought, often repeatedly throughout the month.

As a result, they can add up to hundreds or even thousands of extra dollars. And unlike buying the car or big screen TV, this kind of spending will leave you with very little to show for your money.

How to Fix It: Add up and divide out your expenses for the month to see where your money is going. If you're spending a lot on small purchases, look for areas to immediately cut back, such as by making your own coffee or packing a lunch for work. One of the top tips for saving money is to recognize that $10 purchases do more damage to your budget than $1,000 ones, because they happen all the time.

Money Mistake #3: Using High Interest Debt
If you regularly use account overdraft, credit card cash advances or payday loans, you're essentially throwing money down the drain. Although borrowing can be part of a sound financial plan, these forms of debt are as expensive as they come.

For example, a $50 fee for a 14-day, $300 payday loan may sound reasonable in a pinch, but in banking terms, it actually represents an annual interest rate of 435 percent! Cash advances and overdraft protection, while less expensive, still cost a lot more than other consumer loans or lines of credit. And the more expensive it is for you to borrow, the more likely you are to get behind, borrow more and dig yourself ever deeper into debt.

How to Fix It: The most expensive forms of debt usually come into play when borrowers have few other options, often because poor credit or maxed out debt levels make other forms of borrowing unavailable. So, in order to avoid high-interest debt, borrowers need to work on the problems that lead them to borrowing in the first place.

If you're simply running short of money at the end of each month, work on setting up a savings account, and start setting some money aside for when this happens. And if you have any options besides high-interest loans, always use those first.

Money Mistake #4: Setting Yourself Up for Failure
Making good financial decisions takes discipline and hard work. Just like Olympic athletes who have achieved amazing athletic feats -- do you think they woke up in the morning and just hoped they'd be able to fit in some training? The reality is that great athletes set themselves up for success by planning and organizing their lives to optimize their ability to train.

The same is true for you and your finances. You can't just hope that you won't spend so much tomorrow, or that you'll start investing -- you have to set up an environment that makes these things almost inevitable.

How to Fix It: Rather than relying on self discipline from moment to moment when making financial decisions, put it to better use by setting up rules and systems that will make better choices automatic. This includes setting up automatic withdrawals for savings, keeping a limited amount of disposable income in your checking account and, if you're prone to overspending, keeping credit cards at home. Think of the areas that are often weak points for you and set up systems that favor spending less and saving more.

Related: 5 Steps to Stop Living Paycheck to Paycheck

Money Mistake #5: Denial
The biggest money mistake of all isn't an action, but a state of mind. Whether you spend too much, too little, rack up too much debt or fail to save for the future, if you don't accept your mistakes as a problem, nothing will ever change.

How to Fix It: Your money mistakes are your fault. That sounds harsh, but in reality, it should be empowering, because it means that you have the power to turn things around. Take a look at your financial situation and how the choices you make affect it. If you don't like what you see, resolve to change it.

Mistakes are a part of life, but the most successful people are those who recognize their mistakes and learn from them. If you've made some of these common financial mistakes, you're not alone. But what will set you apart -- and set you on the path toward greater financial security -- is working toward avoiding similar ones in the future. 

This article originally appeared on Go Banking Rates.

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