Rules of Adulthood

I recently got the fantastic audio edition of Gretchen Rubin's magnificent book The Happiness Project. I normally would shy away from such apparently hokey, punchy, trendy self-helpish nonfiction, or more honestly, would read it but pretend I hadn't. However, I recently learned that even my super-intelligent, discerning sister read and enjoyed Eat, Pray, Love, and was thus encouraged to do something which Rubin ends up endorsing in her book: I accepted what I like, and liked it without restraint. I like pop non-fiction aimed at helping people form plans to improve their lives. I like walking around DC listening to my iPod on Saturday mornings. I like reading spiritual books in coffee shops in a variety of DC neighborhoods. I recently combined these myriad "likes," and listened to The Happiness Project while walking several miles one Saturday on my way to coffeeshop-hop my way through C.S. Lewis' The Problem of Pain.
The Happiness Project describes Gretchen Rubin's realization that she was not fully enjoying the fantastic life she has found herself in, and her subsequent attempts to become more mindful, kinder, more patient, and better prepared to be resilient in the inevitable hard times we all will face in our lives. One of the planning phases of her project included making a list of "Rules of Adulthood," or things she'd learned as a grown up that shouldn't have taken her so darn long to understand. Inspired, I'm making my own list of "Rules of Adulthood" and asking for yours. Since I've got a little over two months left before I turn 25 (gulp), I'm hoping/assuming this is a work in progress, but I'm pleasantly surprised by how much I have learned since I've been "on my own" (see rule #4).

Erica's Rules of Adulthood
1. Exercising will always make you feel better than not exercising.
2. Sick days should really only be used when you are sick. Otherwise, it's not worth it.
3. Pee when you have to, as soon as possible.
4. You're never really "on your own." Ask for help, and be honest about your struggles. Your family loves you and wants to help.
5. Complaining is usually not worth it, unless you're proposing a plan for change.
6. Spending a half hour on your appearance in the morning is worth how it makes you feel for the rest of the day.
7. Friendships don't stay friendships on their own.
8. Always call people back
9. It's important to be really good at apologies.
10. You don't need a lot of clothes if you have nice clothes.
11. A good bra is indispensable.
12. You may regret going out drinking, you will never regret not going out drinking.
13. Let your actions show how kind/sorry/trustworthy you are, not just your words
14. Don't have more than three drinks in public in one night.
15. Saving money is very important.
16. It's never too late to fix something you did wrong.
17. Eating healthy, fresh food is worth the extra effort. Eating junky food is not worth how it makes you feel.

What are your rules of adulthood?