I can’t believe my 10-year college reunion is coming up at the end of the month, given how closely I’ve stuck to student life. I visit about 15 campuses a year as an education journalist, and have developed an expertise on student-loan debt and the changing contours of higher ed. And yet being an “expert” doesn’t shield me from my share of mistakes.

I’m not talking about the classic “mistakes” that young adults are said to make these days — moving back home with Mom and Dad, not settling on a career, putting off starting families. Most of these are direct products of serious generational economic inequities: More than nine out of 10 bachelor’s degree recipients borrow for college (an average of more than $25,000 in 2011), and over half of new graduates today are either unemployed or underemployed. Those are hard facts, not individual quirks or signs of a collective character deficit.

I’m talking instead about what you can control: the avoidable missteps made by myself and by many other millennials I know.

Despite this generation’s economic challenges, you are some of the most optimistic, flexible and entrepreneurial people out there. So from my towering perspective of a decade out in the world, here are the five biggest mistakes I made as a new graduate, so you can steer clear.

1. I thought I was done learning.

As a former literature major, I dreaded anything having to do with spreadsheets. But after interpreting international education studies, writing columns on consumer finance and even splitting bills with roommates, I conceded that Excel is actually pretty useful. I also had to become conversant in classical economics, presentation skills and Wordpress for my job.

It turns out that “no more tests” doesn’t equate to “no more studying.” And trust me: the sooner you learn that, the sooner you’ll thrive in the new world of work. Chances are your dream job five years down the road will require skills you can’t even imagine today--it may even be in an industry that doesn’t quite exist yet (augmented-reality tour guide? algae-biofuel helicopter retrofitter?).

2. I chased relationship drama.

You can be with the right person for you even if you’re not in a rush to settle down. I learned that the hard way when I dumped my long-term boyfriend and tried to play the field. Today, nothing in my life is more central to my happiness than my husband (yes, that same boyfriend) and our baby daughter. If you want any kind of lasting partnership, and eventually kids, it pays to get serious about your love life right now, by breaking it off with anyone who is crazy or treats you poorly. This policy, of course, has short-term as well as long-term benefits.

3. I thought “disorganized” equaled “creative”.

I was the kid with a backpack stuffed with overdue library books, and I chose a career that wouldn’t require pressed suits and 8 a.m. conference calls daily. I thought being laissez-faire was the sign of a mind attuned to higher matters. That changed when I got back from a two-month backpacking trip to find a $42 unpaid credit card bill had gone into collection — I’m still paying the consequences on my credit report. Now I live by my calendar and automatic bill pay. It turns out being organized actually frees up your mind for bolts of inspiration.

4. I listened to greed more than my gut.

When I was just starting out, I got a tip from a friend on a freelance writing job. The work (writing encyclopedia entries) was easy and interesting, and the pay sounded great, but something seemed a little off about the man who was hiring me. Long story short, I signed a contract, wrote more than 10,000 words and never saw a dime. Chances are you’re going to end up working for a few jerks in your life, but try not to let desperation overwhelm your best instincts — and don’t believe anything that sounds too good to be true.

5. I started to let inertia take over.

Neurologists say the human brain continues to grow and mature significantly up until the age of 25. And sure enough, it took me until about that age to realize that any improvements to my body, mind and life would require some conscious effort: I started working out regularly, met with a therapist for a year, and worked some de-stressors like yoga into my life. After graduation, there aren’t as many advisors around to help you. You’ll have to make a point of setting goals for yourself and seeking out novel experiences. I can’t promise that you’ll prosper in material things; the odds, quite frankly, are against it. But I can promise a richer life if you realize that any inertia is your own doing, and so is any forward momentum. 

Kamenetz is a senior writer at Fast Company and the author, most recently, of Generation Debt and DIY U: Edupunks, Edupreneurs, and the Coming Transformation of Higher Education .

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