No one ever really feels like a "grown-up." But if you're approaching 40, well, you are one.
And it's high time you refined some crucial life skills, from staying healthy to saving money.
Below, we've listed 20 skills you should master before you enter your 40s.
If the thought of getting into a debate with your boss over how much money you deserve makes you nauseated, you're not alone. It helps to both research and practice, as much as you can stand.
If you're negotiating your salary, the best strategy both for getting what you want and still coming off as friendly is to ask for a range including and above your target number. For example, if you're aiming for a $100,000 salary, you'd suggest a $100,000 to $120,000 salary.
Another trick is to frame your proposal in terms of what you're giving the other person as opposed to what they're losing. So instead of saying, "I want $10,000 for my car," you'd say, "I'll give you my car for $10,000."
Establishing a regular sleep schedule
We know it's hard to hear, but it's helpful to wake up at the same time every day — even on weekends. If you oversleep for even a few days, experts say you risk resetting your body clock to a different cycle, so you'll start getting tired later in the day.
On a related note: Experts also advise against hitting "snooze" and going back to sleep when your alarm goes off in the morning. Instead, hit the snooze button once and use the time until your alarm goes off again to turn on a lamp and do some light stretching.
Making small talk at parties
Chances are good that, if you're feeling awkward about chatting with a bunch of impressive people you've never met, other people are feeling the same way.
But as Marjorie Gubelmann, CEO of Vie Luxe, told Oprah.com: "Even if you won't know anyone and you're feeling intimidated, you must go. Do not stay home. So many people are afraid that no one will talk to them and they'll leave feeling awful — but has that ever happened to you?"
One solid way to improve your small-talk skills — and alleviate some of the pressure you feel — is simply to demonstrate interest in your conversation partner. Ask the person questions, let them talk about themselves, and allow them to teach you something.
Finding and sticking to an exercise routine you enjoy
A professor of behavioral medicine told The New York Times that research suggests people who dislike or feel inept at their workouts are unlikely to continue. So experiment and find an activity you really love, whether that's spinning, Zumba, or weightlifting.
Remember: In your 30s, you start losing muscle mass, so it's especially important to exercise at this time.
Finding your career 'sweet spot'
Brian Fetherstonhaugh, worldwide chief talent officer at The Ogilvy Group, writes on TIME.com: "Your career sweet spot is the intersection of three things: what you’re good at, what you love to do, and what the world values."
He says you should "use your 30s to test out hypotheses," like whether you're skilled enough in one area to make a career of it.
Saving for retirement
Your golden years are inching ever closer — and you'll want to be prepared to enjoy them.
As Business Insider's Lauren Lyons Cole reported, by the time you're 40, you should have saved about three times your annual salary.
Investing your money can grow your savings exponentially — without you having to do much of anything. In fact, Lyons Cole, who is a CFP, reported that "missing out on stock market growth spurts is actually riskier than not investing at all."
Investing in relationships
On a Reddit thread about lingering regrets people have from their 30s, multiple people posted about not spending enough time with their family.
For example, mustlovecash writes that they regret "not spending more time with my parents - walking, talking, travelling - while they were still young enough to actively enjoy it" and "ever, ever choosing work time or personal time over spending time with my wife and children. Children grow quickly, and leave home quickly, and the spouse who remains with you will again become the closest and most important person in your life."
Indeed, according to the Harvard Study of Adult Development, good relationships keep us not only happy, but healthy as well. Interestingly, the study found that quality of relationships is more meaningful than quantity once you hit 30.
Saying 'no' to people
According to Glasrud, the best way to muster up the confidence to turn down a request is to recognize that "[t]here are some things you can never have back. Your time, your health, your virtue, your life.
"Don't mess around with those things. It's fine for people to ask — most likely, in their mind, they're trying to help introduce you to a great person or opportunity or meaningful cause. And it's just as fine for you to say 'no.'"
In some cases, you can even say "no" to your boss — sort of. According to national workplace expert Lynn Taylor, if your boss presents you with a new assignment and you're already overloaded, you might respond with:
"I would be happy to do that project, but what that could mean is that [whatever other project you're working on] will have to be put off until tomorrow, because I was actually going to spend the next three hours finishing that proposal. Would you like me to put that off?"
Keeping a clutter-free home
If you're looking to start de-cluttering, there's a whole movement to support you, inspired by Marie Kondo's "The Life-Changing Magic of Tidying Up." The process starts with a tidying "marathon," in which you keep only those items that "spark joy" — and get rid of everything else.
As Business Insider's Erin Brodwin reported, clutter can be a source of stress for some individuals and families. Then again, people tend to be more creative in messy environments — so if you aren't feeling motivated to re-organize your entire office space this second, that's probably okay, too.
Writing on Quora, Vishwa Sharan advises 30-somethings to develop hobbies. People "forget that there is a beautiful life outside of their work," Sharan says, and it's important to find non-work activities you can pursue for the rest of your life.
If you're looking for ideas, check out this list of hobbies that successful people practice in their spare time, from bridge (Bill Gates) to playing the ukulele (Warren Buffett).
Making new friends
In case you haven't heard, it's not so easy to find BFFs once you're off a college campus. That doesn't mean it's impossible — in fact, there are plenty of science-backed strategies for forging friendships in adulthood.
One way is simply to do activities you enjoy so that you meet a steady stream of people with similar interests. Another way is to make yourself a little bit vulnerable: Exchanging confidences as a relationship progresses can make two people feel closer.
As the late psychoanalyst Hedda Bolgar told Oprah.com when she was 103 years old and still practicing: "It's important to be part of a community!"
Failing — and getting back up again
Over on Quora, Mragank Yadav says it's important that 20-somethings learn how to fail, and more importantly, how to get back up again: "Failing comes naturally. Rising up again is something that needs to be [inculcated]."
Yadav's insight applies just as well to people in their 30s.
Take a tip from now super-successful figures, like Paul Allen and Oprah Winfrey, all of whom learned from multiple professional failures.
Living in a chronic state of stress and exhaustion can take its toll on you physically, mentally, and emotionally, and if brought on by work it can lead to job burnout.
You won't make it that far in your career if you don't pick up some strategies for managing stress — even seemingly simple strategies like listening to music and exercising can help.
The fact that it may have been ... a few years since you've set foot in a classroom doesn't mean you should stop learning.
And don't limit yourself to subjects that would have an obvious impact on your career. After dropping out of college, Steve Jobs still audited the occasional class, and one course he took on calligraphy was a huge influence on him and inspired "the wonderful typography" personal computers have today.
Proper time management is a skill you should have down by the time you hit 30, says Barry S. Saltzman, a business-strategy expert who is the CEO of Saltzman Enterprise Group.
So for 39-year-olds, it should be a given.
You may get away with being all over the place as an intern, but it's not cute when you're leading the team and you can't get your own act together.
Time is money, Saltzman points out, and no company will be happy with needlessly wasted money: "Learning by 30 what makes you efficient is important to professional development, and beyond that, improved efficiency makes you look a lot better in the eyes of your superiors."
"Have you ever truly figured out how to cook?" asks Sachin Shubham on a Quora thread about important things to do in your 20s.
As in, maybe you can feed yourself and your family with spaghetti and omelets, but what would you serve at a fancy dinner party? Sign up for a course and learn at least one dish so you can impress guests with your culinary expertise.
Knowing your personal values
Don't let other people define happiness and success for you. On Quora, Anna Lundberg writes:"The number one priority at this stage [30 years old] is getting clarity on what your priorities actually are!
"A great way to do this is to define your personal values, getting to a list of your top three is ideal. Then ask yourself if these values are really reflected in your career and your lifestyle today. If not, you can go about setting goals that are aligned with those values, and then creating an action plan to achieve those goals."
You can also take a tip from Stephen Covey, author of the bestseller "The 7 Habits of Highly Effective People," and craft a personal mission statement. It's similar to a company mission statement, except it's just for you.
Covey wrote: "It focuses on what you want to be (character) and to do (contributions and achievements) and on the values or principles upon which being and doing are based."
Once you understand your own career vision, you must figure out how you will explain it to others.
"Sharing that you're a copywriter or that you work in finance is fine and dandy, but it doesn't make you stand out or inspire people to want to ask you follow-up questions," says Michelle Ward, a creative career coach and coauthor of "The Declaration of You!"
Instead, when people inquire about what you do, answer with your "what," "who," and "how." Don't be afraid to mention what you're passionate about, the types of people you help, and what you do for them specifically, she says.
When Ward introduces herself, she tells people that she offers dream-career guidance for creative women. "That way, the person listening can connect with what I'm saying or introduce me to any creative women they know who are looking for dream-career guidance," she says.
Being happy with what you have
"If you are content with what you have, you will have a happier life," says Robert Walker on a Quora thread about things to do at 30 to benefit yourself later on.
That's especially true in the relationships domain. "The Gratitude Diaries" author Janice Kaplan found that simply saying "thank you" to her husband breathed new life into their marriage. And psychologists have found that couples who express gratitude toward each other are more likely to stay together.
Forgiving yourself for your mistakes
"Forgive yourself your mistakes. We all make plenty of them. Don't dwell on the errors of the past — learn from them, let them go, and move ahead," writes Liz Palmer in a since-deleted Quora post.
In "The Happiness Track," Emma Seppala, science director of Stanford's Center for Compassion and Altruism Research and Education, argues that self-compassion is a key component of success. If you're kind to yourself when you fail, you have a chance at learning from your mistakes and doing better next time.
She recommends a simple strategy for exercising self-compassion: Treat yourself as you would treat a colleague or friend who has failed.
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