Age is but a number. One can be young at heart. One can be an old soul. Blah, blah, blah.
Still, it's hard to deny that a person's 20s are generally more carefree than their 30s. But when you're in your 20s, it can be hard to know how to fully take advantage of your youth.
If you haven't hit 30 yet, hit up this r/AskReddit thread for some ideas on what to do with your fleeting youth.