Welcome to another installment of iontuition’s Q&A series with personal finance bloggers. We have Money Under 30’s David Weliver sharing his financial advice with us today. His blog, Money Under 30, is devoted to providing free financial advice to young professionals.

Prior to starting his blog in 2006, David worked at a financial magazine called SmartMoney but was dismayed that all the financial media out there was only written for older people, who had money to invest and spend, unlike most young people! David also stumbled a bit managing his own money, so he used the website as a place to talk about his mistakes and chronicle how he fixed them.

What’s the best piece of financial advice you ever received?

This is going to sound odd, but I don’t recall receiving much financial advice that stuck. My father was always talking about the value of a dollar and not spending when I was younger, but by the time I was old enough to start paying attention, my parents hit some hard times and, frankly, didn’t set the best financial example going through them.

Working at SmartMoney, I started reading the collective wisdom of all the writers there, and began to see the value of investing and, most importantly, spending less than you earn. That’s when I started to change.

What’s your advice for those who already have student loans?

Student loans are a fact of life for most young people today. For most people, they’re just another financial obligation to deal with. While you’re paying them back, you’re simply going to have to adjust how much you spend on other things. It might mean driving that old car a few more years or living in a cheaper apartment.

The problem arises if someone has so much student debt that they can’t earn enough to pay it back AND meet other expenses. If you’re struggling, definitely look into deferment and income-based repayment plans, but you may also have to step back and reevaluate your career. It sucks, but many people go into a lot of debt to pursue a low-paying career. Sometimes you may have to do whatever it takes to get higher-paying work to repay those loans.

How do you stay ahead on paying your student loans back?

Like I said above, it’s about knowing what you owe and making sure that your student loan payments don’t represent too large a percentage of your monthly income. If you earn $2,000 a month after taxes and your loan payments are $200, that’s 10 percent and probably manageable. If the payments are $400 (20 percent), that’s tougher. And if your debt payments start to exceed 30 or 35 percent of your income, you’ll have a tough time. You have to adjust something – whether it’s your payment through IBR plans or refinancing your loan, or your income, by getting a second job, for example.

If you could go back in time and give your 18-year-old self a piece of financial advice, what would it be?

Ha! Just one. Where do I start? Well, it would have to be the utmost importance of spending (a good deal) less than you earn. I just didn’t get it. I bought stuff on credit cards in college just figuring (I’ll have a good job when I graduate and can just pay this stuff off.) Not so easy. The problem is, even a few months of overspending makes it that much harder in the future because you’re still paying for last month. Years later, I also see the freedom that you have when you don’t have debt, you’ve saved something, and you spend less than you earn. That’s so powerful.

Would you go to a different school if you knew what you know now about student debt?

That’s a tough one. Possibly. I did go to an expensive private college, but I got lucky that my student debt wasn’t outrageous because I received aid in the form of grants and work-study. My parents borrowed, too, however, which I feel bad about. If I hadn’t received the aid I did, I couldn’t have afforded it, period. With the aid, it was manageable. I’m not going spend too much time second guessing my college choice, but I am already leaning towards suggesting my kids go to in-state public university!

Any other financial tips for our readers?

It’s especially hard when you’re just starting out and need to obsess over every dollar, but if you can begin to see the money you earn in terms of free hours it could one day buy you, it will become easier to curb your spending. Any time you’re pondering a significant expense, consider how many hours you would need to work for that money. Then, imagine if that money could buy you that many hours (or days) of totally free time — no work, no responsibilities. If the amount of time excites you, maybe that money is better invested.

Read more from Money Under 30 on his blog, visit him on Facebook and follow him on Twitter.