Hindsight is 20/20. In honor of National Financial Literacy Month, I want to identify some things I wish I knew about money before entering adulthood.

By thirteen, I was a pro at balancing a checkbook and enjoyed doing it (gasp!), but I actually had no idea how money, debt, and savings really worked. As a result, as soon as I turned legal age I began interacting with debt and spent the next fifteen years living beyond my means.

If I could go back to my eighteen-year-old self, these are the things I would make sure I knew.

15 Things I Wish I Knew About Money Before Entering Adulthood

1. That a credit card is not “free” money.
2. How borrowing for college would affect my life and career choices as well as my future family.
3. To live on less than I make.
4. To plan my spending by living on a budget.
5. Not to live for today at tomorrow’s expense.
6. To start saving for retirement right away.
7. To start saving for kids’ college, the minute they are born.
8. The Joneses are broke and keeping up with them will make me broke too.
9. To save up to buy real estate early.
10. To live within my means. Not to use debt to elevate lifestyle.
11. Not to increase lifestyle with every single raise or promotion.
12. If I can “afford the payment”, then I can afford to wait and save up for it.
13. It’s okay to say, “I don’t have the money for ________.”
14. Sometimes I will need to tell myself and others no (and that’s okay).
15. Other people struggle with money too and are relieved when you admit you are.

We can’t go back in time (at least until time travel is invented), but we certainly can learn from our past mistakes. And we can share those lessons with the people in our lives. What’s the point of making mistakes if someone’s not learning from them, right?

How about you? What do wish you knew about money before becoming an adult? Enter in the comments below.