As I turn 30, there are a few things I wish I knew a decade ago.
1. Credit card debt is not good. A credit card is a tool not to be abused. Don't carry a balance.
2. An emergency fund is a necessity.
3. 4 years of college will go by so fast. Use every opportunity. An unpaid internship is not a bad thing. Let no opportunity pass you by, it is not all about money.
4. Network, Network, Network. Those contacts will be invaluable in the future.
5. Don't stress about your undergraduate major. You may not even use it directly in future jobs. The world doesn't stop if your major isn't declared by sophomore year.
6. Men come and go. Period. The End.
I will add to this list as time goes by.