Recently, a student asked me for some tips on what to say about personal finance to her sorority. Here’s a slightly-edited version of my reply.

1. Count the Cost Accurately. You might think you’re saving money when you’re not. Unless you really enjoy cooking, you should probably have a meal plan and devote the time and energy you save on shopping and meal prep to studying. Look at the BLS Occupational Outlook Handbook for the job you want, look at the hourly wage, and use that as a proxy for what your time is worth right now.
2. Treat Every Action as an Investment. Choose to do more things that have a positive rate of return (studying, reading, getting better at math, exercising) and fewer things that have a negative rate of return (social media, most things that seem URGENT URGENT URGENT NOW NOW NOW but that won’t matter in twenty years).
3. Spend Less Time Around Jerks. which means that yes,  you might need to dump your significant other. It has been said you are the average of the five people with whom you spend the most time. You should love and pray for jerks, of course, but recognize that the opportunity cost of indulging them is the help and service you’re not providing for others. This will likely pay off down the road in some combination of higher earnings and more peace of mind. That tension you’re feeling right now is probably what the economist James M. Buchanan called “The Samaritan’s Dilemma”: jerks obviously need help, but the more you put up with and indulge jerks, the weaker are their incentives to shape up. It is hardly clear, therefore, that putting up with jerks helps the jerks themselves. How to proceed, I think, varies from case to case, and here is where consultation and coffee with friends and mentors becomes super-important.
4. Open a Roth IRA. There are a lot of low-cost mutual fund providers out there; Fidelity handles my employer’s retirement accounts, and my family also has some money with Vanguard. With a Roth IRA, you invest post-tax income and then never pay taxes again. That’s a great deal right now, while you face a very low marginal tax rate, and you have a lot of time to enjoy the benefits of compound interest. There is a credible commitment problem here: it will be hard for the federal government to resist the urge to go back on its promises and double-tax accumulated Roth wealth.
5. Once you Have a Job, Enroll in Your Employer’s Retirement Program. Save somewhere between 15% of your salary and the maximum contribution.
6. Ask For a Raise. As another student pointed out, there’s some evidence that women don’t get raises and other workplace perks because they don’t ask for them. You can probably get more than you think.
7. Give Generously. As a colleague once pointed out in a lecture on “How to Be Rich,” it’s not so much about what the money does once you’ve given it, but about a regular test of your trust in God. Giving is centering: it is, in some ways, a sermon you preach to yourself about the nature of faith, hope, and love.
8. Consume less. Moderate your tastes. Pay for quality and convenience, but recognize that a lot of things you buy just add clutter to your closet or calendar. Preemptively KonMari your clutter by not buying half that junk in the first place. 
9. Other People Are Making Their Choices With Very Different Information, Goals, Beliefs, and Preferences, So Give Them the Benefit of the Doubt. “Consume less” mileage varies. Maybe that brand-new car your roommate just bought is an investment in not having to worry about anything other than routine maintenance for the next few years. You can rationalize anything, though, so listen carefully to the people who love you. If someone asks you whether or not you really need a supercharged sports car so you can try to break the record for the Cannonball Run, you should listen carefully as you’re probably not making an especially prudent decision.
10. Say “no” more often. Just because the world would be a better place if something were done doesn’t mean you’re the one to do it; moreover, a lot of our charitable efforts probably don’t help as much as we think they do.

Reprinted from Forbes