As of Tuesday, August 30th, I will be twenty-one years old. In the scheme of life, this is the most important birthday I've had so far, and not just because I finally have a sideways license (thanks, New Jersey). Twenty-one is the age when you're officially an adult. And while paying for insurance and trying to find a job before I turn 22 terrifies me, I feel like I've got it at least a little bit together. So here are 21 things I've learned before I turned 21 that I'm now passing on to you.

1. When someone invites you somewhere, that means they want you to be there. They're not just being polite, they wouldn't invite you if they didn't want you there.

2. Listening to someone talk about something they're passionate about is one of the most amazing experiences because the joy they experience in their obsession automatically comes out when they're describing it.

3. You don't have to ever define your sexuality, you can literally just be you for your entire life.

4. Nothing is more painful than watching someone you love get sick, and never get better.

5. Don't declare your major until you're sure about what you want to do, because you have so much freedom before declaring and once you declare that freedom goes away a little bit.

6. Your value is not based on the number of relationships you've had or the people you've hooked up with.

7. When you wake up in the morning, do this. Trust me, it'll make you feel better.

8. Don't go with the easy path just because you know what's going to happen. And on that note...

9. Do the things that scare you, whether it's going zip-lining even though you're afraid of heights, or joining the sorority none of your friends are in, you won't regret it because...

10. You only regret the things you don't try.

11. Don't apologize for loving something. It's not a problem if something makes you happy (unless it's meth, and then please go to the doctor).

12. Literally, no one at the gym cares what you're doing, they're all too busy trying not to die of the pain that working out causes.

13. Gender is a social construct, and you don't have to conform to the gender you were assigned at birth.

14. Don't let people tell you that you can't do something just because it's never been done before. Do it.

15. You don't have to hate your parents. Your mom literally pushed you out of her vagina, if that doesn't call for unconditional love, I don't know what does.

16. Find at least one TV show or book or movie or song that always makes you happy, because sometimes you just need a place to escape to when the world is too mean.

17. It's okay if home isn't the same when you come home from college, and it's okay if college is your home now. You spend most of your time there anyways, and your parents are happy that you're happy. (Or at least I hope they are; I have really great, supportive parents who would let me stay at college all year long if I wanted (which I do but ORS won't let me)).

18. You're allowed a cheat day from your diet. It's not going to ruin your life.

19. Do not feel obligated by toxic people. You are not required to spend time with people that are horrible. The most important thing you can learn is that "The blood of the covenant is thicker than the water of the womb", so the people who you love and who treat you well are more important than people that you just happen to share DNA with but treat you horribly.

20. If you can say that you're proud of at least one thing you did today before you go to sleep, then you had a good day. And finally...

21. The mitochondria is the powerhouse of the cell.