1. Stay up all night.

There are no fewer than a billion reasons why 20-somethings frequently stay up all night. A non-exhaustive list:

Studying.

Making out for hours because you haven't slept together yet and aren't sure if it's time to cross that line, so you just make out until 5 a.m. and it's like, "Seriously, we should've just had sex and then slept."

Actually having sex.

Waiting for your roommate to come home because your phone died and you forgot your key.

You didn't realize how long that molly you took would keep you awake.

Drinking. Drugs. Duh.

Safe to say, regardless of whether you're a bookworm, a binge drinker, a bed-hopper or some glorious combination of all of those, your 20s is a time when you have an excessive amount of energy and a huge list of unaccomplished goals during a window of time in which it is considered perfectly acceptable to be self-obsessed in the healthy, good way that people are when they're trying to build a life for themselves. This often leads to a number of late- and all-nighters. Babies operate on ridiculous schedules for the first weeks and months, like a bunch of squishy meth heads. Which means you will likely have many late nights. Luckily, all those long nights -- whether you were being a hardworking student or a wild child -- that your mom told you were unhealthy were actually getting you trained for being a parent who could stay up all night and still be mostly human the next day.

2. Take care of your friends.

Everyone knows that you typically have three kinds of family in your life: the one you're born into, the one you create with your friends and the one you make with romantic partners and maybe babies. You create the second family to replicate the security and comfort of the first, and the second ends up teaching you how to be generous and loving in your relationships -- which is exactly what you need for your third family. Those nights you listen to your best friend cry about a breakup, you learn how to be there for someone. When you do that without saying things like "this really isn't a big deal" or "I told you that he/she was no good," you're learning how to empathize and let people who maybe have less perspective than you just feel what they're feeling without policing or lecturing them -- which is what you do with kids.

We hold our friends' hair when they throw up. We bring them food and watch Netflix with them when they're sick. We console them when they're disappointed. We nurture. We coddle sometimes, and sometimes we hand out tough love. We push -- but not too hard. We help our friends -- and they help us -- become better, happier, more evolved people. You will be amazed by how much your relationships with your kids will mirror that. And, as a side note, once you realize that, you also get another crucial parenting point: your kids, even in their weak moments when they need you, still have a lot to teach you -- and they take care of you as much as you do them.

3. Clean up vomit.

Managing a barfy baby will require skills that hark back to the time when your neighbor's boyfriend, who wasn't even invited to your party but showed right the f*ck up anyway, had 12 jello shots and puked on your rug.

4. Make minor repairs to your apartment.

There was definitely a long period of time in my early 20s when, if something wasn't perfect about an apartment, I wouldn't hang around to try and fix it; I would just cut my lease early and move on to another place. You could also replace the word "apartment" with "relationship" in that scenario and it would be equally true. But then something shifted; I stopping quitting things. If I had a bad day at a job, I didn't immediately start looking for a new one. If a pipe was leaking in my apartment, I emailed my landlord instead of cruising Craigslist for a new place. When a person showed themselves to be flawed, as everyone will eventually do, I didn't dismiss them. I learned to adapt without sacrificing too much of myself. I learned to mend wounds without trying to force change. I came to accept -- and even love -- imperfections and awkward edges. And as a result, I started getting to see all the infinitely better things that come along with building a history in a place, or with a person.

When you have a kid, you can't quit. You won't want to, but you can't anyway. And when you realize that -- that you have to stick around and love this new person, no matter what -- suddenly all those small choices to stick with things, and not be so rigid about your life and your expectations of what things should be like and how people should perform, will take on a huge new meaning.

These are the small choices that, in the end, leave you knowing how to feel comfortable with the idea of inescapable obligation. They leave you with the capacity to love something imperfect -- because babies are imperfect as f*ck, as far as humans go. Their skull bones aren't even fused. It's a disaster. But once you're in, you're in -- it'll be better for both of you if that relationship wasn't your first attempt at commitment. We think of "learning to commit" most often in terms of a romantic relationship, but that's just Hollywood distracting you from the fact that life is way more complex than that. When you think about it, you'll realize you've spent years learning how to do it.

5. Learn to prioritize when you have way too much to do.

Twenty-somethings and parents already have one stereotype in common: They are too busy all the time. There is never enough time for everything you want to do in a day. When you're in your 20s, you have school, friends, work, dating, traveling, maybe sleep sometimes -- and there's never enough time. So you learn to prioritize. You figure out what's most important and you put your energy there. You learn to not sweat it so hard when some things don't get done, because if you do, you end up not enjoying your life, and then what the f*ck is the point of doing any of it? In your 20s, you feel incredible pressure to achieve so much so quickly in terms of your career, your social life, your education and your personal development into an awesome individual. Parenting (not news to anyone) comes with just as many bullsh*t pressures -- so it's a very good thing you're already used to saying "f*ck all that" and figuring out for yourself what really matters.

6. Have one-night stands.

Stay with me here: It's about being present in the moment and not worrying about the past or the future. It's about giving yourself up to the incredible joy of something happening, without needing to understand how it's part of some big-picture plan. It's about valuing single, beautiful experiences just as they are. It's about knowing how to accept the intangible, impermanent nature of a lot of things, and being able to let them go even if they were amazing. Babies grow up. They do it annoyingly fast. Learning how to enjoy a moment without becoming overly attached to it is fundamental to feeling good about being a parent. You know how stressful and unpleasant sh*t gets when you try to force a one-night stand to be something more when it clearly should not be? You know how some parents can't deal with their kids growing up so they try and force them to stay young and dependent? I have felt both of those things, and I'm telling you: they are basically born from the same inability to accept the changing nature of things. If you learn how to have one-night stands with a healthy attitude, you are very likely going to use that same attitude when you have kids. And your kids will thank you. I mean, they might not thank you for boning a bunch of randoms. Maybe skip telling them exactly how you got to be so awesome.

7. Ask your parents for money.

I refuse to play into the largely untrue stereotype of 20-somethings constantly depending on their parents for money. The overwhelming majority of people I know don't do that, and honestly, who the f*ck imagined this blissful world where all of our parents actually have money to give us? Although -- let's be real -- a lot of us have occasional moments when we are indeed about that "mom, haaaallllp me" life. It seems illogical to think that leaning on your parents somehow teaches you something vital about being a parent, but it does!

Watch the wheels of justification turn, pets: You learn how to ask for help when you need it. At some point, despite all of your efforts, you won't be able to be entirely self-reliant -- you'll get a flat tire and need a ride, you'll be super sick and need someone to bring you food because you are literally incapable of making it, you'll unexpectedly get fired and need a little extra money to make rent... however it happens, everyone (not just 20-somethings) has to lean on their people occasionally. It doesn't make you weak -- it makes you mature and secure enough to know that gathering awesome, trustworthy people around you is an arguably bigger accomplishment than doing everything yourself. When you have kids, knowing when to ask for help or take someone up on their offer to help can mean the difference between your and your kids' lives functioning smoothly, and everything being a frantic mess. Being a good parent has everything to do with getting over your hang-ups -- stubbornness, your ego, etc. -- enough to do what needs to be done to keep the important people in your life (including you and your kids) taken care of, physically, emotionally and in every other way. This often means knowing how to ask for help without feeling like a failure at life. If that ain't a 20-something life skill, I mean...

8. Make healthy food with minimal money/effort/cooking skill.

Can we all agree that everyone's very first "I'm getting so old" moment comes relatively early in your 20s when you reach a point where you've been consuming an entirely unhealthy diet for a shamefully long time, and you finally actually feel like total sh*t because of it? Like, you physically feel the effects of not giving your body vegetables. Childhood notions of being able to live off of Pop-Tarts and popcorn evaporate in the harsh light of the impending decline of your rapidly aging body. So you decide to eat real food, but like, in the laziest way, and for the least amount of money imaginable. Twenty-somethings are ninjas about getting a reasonably healthy diet on modest incomes and with few culinary skills. We were coddled and fed for our whole lives on food we didn't have to cook or pay for, and now we're out here in the harsh world and we think we're getting an ulcer and what the f*ck, we're only 21, but by God, we're gonna figure out how to not die of malnutrition.

By the time you have kids in your life, ideally things will be less dismal than that. Clearly. But when you're tired from being too awesome during your long day of being awesome, or your kids are blowing through an unprecedented amount of expensive organic groceries, or you're sick and you start to get the feeling that if you don't feed them soon, they will start to eat you -- you'll find that all of those tricks you developed as a youngish, poorish person will still work perfectly.