1. Speak up more.
As the saying goes, it's the squeaky wheel that gets the grease. You are your one and only true advocate, so never be afraid to stand up for yourself and speak your mind, because regret's a b****.
2. Know when to walk away.
Many readers voiced that walking away, while it may be a difficult decision, is sometimes the best thing you can do for yourself. And the quicker you can come to this realization1, the more you can save yourself from making up for lost time.
3. Save more money.
Retirement2 is no joke, as you'll learn by 50. As you stare at the bleak3 reality of your 401K, you might find yourself counting every nickel and dime4 you wasted on frivolous5 expenses. So pack your lunch, find street parking (or take the bus) and remember that a penny saved is a penny earned, as cheesy as it sounds.
4. Re-think a college major.
A few readers mentioned how they wish they'd re-considered their choice of college major, or even thought twice before dropping out.
5. Travel more.