It is a bucket list, of sorts... I have done all of these things and they have all changed my life in some way. I have come to believe that all of these things are somewhat essential in this whole 'growing up' thing.
1. Get on a bus or a train with no destination. Get off when your money runs out, or you reach the end of the line. You never know what you'll find
2. Work a service job. This will teach you the value of a dollar; a friendly hello; and a grateful goodbye
3. Open a savings account. Save a small amount every single week. This could be anything from $10 to $50 -- but refrain from taking money out of it. You never know when you're going to need it.
4. Read a book. At least one, each year. Make it something that challenges you.
5. Kiss a stranger. Don't get their name. Don't get their number.
6. Learn to say 'no'.
7. Find something that makes you feel talented and unique, and do it ALL THE TIME.
8. Go to the cinema, to a restaurant, or to see your favourite band completely alone.
9. Find a way to differentiate between the people who are in your life because you want them there, and people who are in your life because they never left. Get rid of the people who weigh you down: those who make you feel unworthy or undeserving. Realize that time spent alone is a hundred times better than time spent with those who make you want to hurl all down yourself.
10. Start taking yourself seriously. Your twenties are not the between time for 'figuring things out'. It's OK if you don't have things figured out yet (99% of people don't), but that doesn't mean that you're up for ten wasted years until you hit thirty and can reasonably have an existential crisis.
11. Embrace the pain. Suffering is universal. You have to be open to the suffering to even give yourself even the slightest shot in hell at happiness: and most likely, you will never get one without some degree of the other.
12. Understand that travel is the only thing you can buy that will make you richer. That Louis Vuitton bag or Chanel lipstick are not going to enrich your life the way you imagine.
13. Own a pet. Or a plant. Take responsibility for something other than yourself.
14. Live alone, in your own apartment
15. Be unemployed - if only for a week
16. Party until the sun comes up: get breakfast on your way home. Also...
17. Go to a world famous party. Be it Oktoberfest, Mardi Gras, Carnaval, Ibiza… I don't care. Just go to one to understand the feeling of mass enthusiasm.
18. Learn how to cook. At least one thing.
19. Write someone a love letter with a pen and a piece of paper: not a keyboard and a gmail account.
20. On a similar note: Write yourself a letter to open in ten years time. Include your passions, goals, and expectations for the future: both for yourself personally, and the world around you. That way, you can still surprise yourself when you're pushing 40.