{ Repost: The 10 Most Important Lessons For 20-Something Workers }

1. How You Spend Your 20s Will Define You

According to Meg Jay, Ph.D., a psychologist and author of The Defining Decade: Why your twenties matter--and how to make the most of them now, many 20-somethings believe they have all time in the world and how they spend their 20s doesn't matter. But Jay says they matter most. The foundation you build in your 20s will define the rest of your life. Take yourself seriously, she urges.

2. Adult Responsibilities Make You Happier

While many young people may resist getting a "real job" or becoming independent, Jay says these are the things that make you happy and give you purpose. "Some people underestimate the satisfaction of working, thinking they’ll be miserable in a cube," she says. "The 20-somethings that do work are happier than those who don’t or are underemployed."

3. Get The Best Job You Can Get

If you invest in your career early, you'll have longer to build it up. Jay says that 70% of wage growth happens in the first 10 years, so you need to get the best job you can get and negotiate your salary. "People who wait until their 30s to get going are never going to catch up."

4. Not Making A Choice Is A Choice

Jay says many 20-somethings don't know what they want to do, so they hang around the house or in low-level jobs waiting for the spirit to move them. "Not making a choice is a choice," she warns. "These 20-somethings think they are keeping their options open, but they are actually closing doors." Resumes start look thin, their peers begin surpassing them and they may get stuck in underemployment. 

5. It's Going To Take Time To Get Good At Your Job

Jay tells her 20-something clients who are fresh on the job scene that it will take about 10,000 hours (or about five years) to really master their jobs. If you're wondering why colleagues seem so poised and confident, it's partly because they've been doing it longer, she says. She advises young people to learn as much as they can in their first jobs and remember it will take some time to really get good.

6. Get Some Perspective

The 20-something brain is still developing its frontal lobe, says Jay, which is in charge of overriding emotion with reason. This, coupled with less on-the-job experience, means 20-somethings are more sensitive to surprise and criticism. They are more likely to take feedback personally, and magnify events to enormous proportions in their minds. Step back and get some perspective, advises Jay. You're not going to be fired because your boss is angry. Hear the criticism and learn from it.

7. Take Romantic Relationships Seriously

Just because many are marrying later doesn't mean love in your 20s should be waved off as unimportant, says Jay. She views the 20s as the time when you should be learning how to have healthy relationships. That means dating people who have the attributes of a long-term partner, and not putting off love just because you think you can or should.

8. Think Hard About Cohabitation

Cohabitation has increased by 1,500% since 1960, says Jay. Today 7.5 million unmarried couples live together, and more than half of all marriages will be preceded by living together. However, Jay warns that too often young couples don't communicate clearly about what cohabitation means for their relationship. "It's easier to get in than get out," she warns, noting that cohabitation can lead to marriages that aren't compatible because it becomes so difficult to untangle.

9. Start Family Planning Early

Not a whole lot of 20-somethings are thinking about fertility--but they should be, says Jay. She notes that young people have been told that they have all the time in the world to start a family. In reality, fertility starts dropping significantly by age 35 and dramatically by 40. It's not just a woman's issue either. Older sperm is associated with problems, she says, and it certainly impacts men when their spouses can't get pregnant. Jay says you don't have to start your family in your 20s, but you should be aware of medical realities and plan ahead.

10. Change Your Brain For Life

Jay says the brain doesn't fully mature until your mid-20s, particularly the parts that plan for the future and manage emotions. That doesn't mean you should sit around and wait for it to develop, she says. In fact, what you learn and experience in your 20s becomes hardwired into your brain, and this is the best chance you have to re-wire your brain and change how you think and react. "What people do in their 20s wires who they’ll be as adults." 

[Source: Forbes]