I've been giving this list some thought over time, and though this is only a portion of them, but here we go.
1. Trendy Tattoos
If there is one thing about tattoos that makes my brain nervous is that 99.99% of them are born out of and defined by some trend. I think with enough experience you could train a monkey to identify what time period and under what conditions a person got their sweet tat. We've all heard a story like, "Oh ya, I was belligerent drunk one night and since that's when I catapult into my high quality decision making mind-state, that was when I got my tattoo of Optimus Prime fighting the Ninja Turtles over who liked Chuck Norris the most on my lower back. I thought it'd be cool." Wrong. Have fun explaining that one to your grand kids who are going to be asking you to tell them stories about the days when you "used to use paper." Don't be that guy or girl. And while we're on the subject let me settle the bet for you: Forget Chuck Norris. Mrs. Pacman wins the awesome award 1000% of the time, don't even bother arguing with me.
2. Mullets
It's said that a mullet is business in the front and a party in the back, but it should be more accurately described as a face-to-face debacle you lost to an angry mexican gardener with a weed-eater. Let's face it, mullets aren't cool. You just need to choose a hair length and roll with it, you can't just say "I choose both" and think we as society will accept that as a legitimate answer. You're clearly not very good at making decisions, but is that really a character trait you want to flaunt on your head? For shame.
3. Not taking risks
Anything worth doing is a little risky. Think of all the companies that would have never started if investors didn't take risks in a huge way? I don't even want to attempt to fathom the amount of pop-ups I would have had to wade through during the process of trying to write this post had some big money millionaire not invested money in funding the start of Apple. Go do something scary. Jump off of something. Drive too fast at least once. Go do something you should only do in a group. Challenge yourself. Find out what is the max you can handle of something and then do it just a little bit more. Do something you would watch someone else do and say, "That guy's an idiot for doing that." It's good for you, and it gives you a memory to look back on.
4. Not Traveling
Trust me on this one, I've yet to travel as much as I would like to, and it's already becoming more difficult than I'd like it to be. There will never be a time in life when it's more simple for you to drop whatever it is your doing and go. There's so much more world than you've seen, and just because it's more cozy in your room, or you know the streets around your town and that's enough for you, suck it up and go explore. It's worth it to have the adventures and to learn how other people experience life differently from you.
5. Video Games
I know logging in every late at night and playing the joint campaign until the morning sunrise with guys from Germany and Albania is totally awesome but winning that Tricidian 3-edged up-angled spirit sword is not only lame, but also dipped in a vat of real-life-friend retardant. The amount of time you spend playing video games is only that, time spent. Sure you can say it improves your "hand-eye coordination" but really it's just going to melt your corneas and give you carpel tunnel. Your Xplay-Weestation-Box is not going to get you a job testing video games. Sorry to be the bearer of bad news.
6. Not Getting Married/Getting Married
This one could go either way. I think it goes without saying that "when you should get married" varies for each person. I have friends from high school that I know will never get married because they love WoW, Magic the Gathering, and beer pong too much to ever grow up and do something with themselves. However, in the same way I have friends who were ready to have a wife, 9 to 5 job, a house with a picket fence, and 2.5 kids as a package deal with their high school diploma. Make sure you are getting married for the right reasons for you, and not for anyone else. Either way it's worth the wait/rush.
7. Inappropriate Internet Photos
This one doesn't need much explanation, but no matter what you do with your life, you'll never be proud of your lack of "facebook upload discretion" from the "good times" from your youth. Good luck explaining those same principles to your kids while those not-so-kodak moments exist forever frozen on facebook or the futuristic equivalent (remember Myspace? Ha). For your sake, your future kids, and my future kids, be wise, don't be an idiot, and don't be trashy. Period.
8. Smoking
Oh Tobacco and your manipulative controlling ways. You're like the mother-in-law everyone dreads, yet people choose you. I bet you feel so cool when you exhale that smoke out of your nose. It won't affect you right? And you know what isn't that cool? Chemo and radiation. It's not gonna feel so awesome when you can't even get out of bed and your lungs (if you still have them both) are blacker than african sin at night in a cave. It's also gonna be cool when you're kids are stealing your last pack of Marlboro lights out of your glovebox with their stubby six year old fingers. That jank will kill you, maybe not 'right now' but it will, so cut it out.
9. Not Volunteering
Let's get serious for a second—there's something about selflessly giving of yourself that is written into the human nature of DNA. However, in our world of self-preserving pretentiousness that has turned us into time/effort/resource/money hoarding buffoons that can't see past the end of our noses, doing something for someone else out of the pure kindness of your heart will never return void. I promise.
10. Tanning Beds Many have lied to themselves and said "I just want a base tan so I can look hot in (insert article of clothing here)". But let me be the first to tell you that it's gonna be hard to say that when you look more like a dried shammy or an old leather briefcase in your 50's. Prepare yourself now to not be an aloe vera dependent hot mess of skin cancer later. A little extra darkness now is not worth it.
11. Bad Credit
That Louis Vuitton matched luggage set is not an investment no matter how you spin it. Don't confuse something you want with something you don't need. Having bad credit will only make your life difficult in nearly every way. Frivolous spending, though promoted in our culture is not the way to happiness. Pay your bills on time, don't buy useless crap you can't afford, and for goodness sakes get a savings account that isn't shaped like a piggy on your dresser.
12. Being Lazy
This one is nothing but a choice. I can't think of one person that sits at home all day, covered in cheetos, watching infomercials about knives that can cut through shoes and exhaust pipes that is doing something meaningful with their lives. Do something people. Be passionate about something and do everything you can to achieve it. We live in a world that tells you to relax, do nothing, take time off, and don't do more than is asked of you. While I agree there is a time for that in life, it's no way to live your life. While you sit on your couch watching PBS trying to mimic the sound of a weasel's mating call to impress your sister, I'll be working on something worthwhile so I can make something of my life for a purpose bigger than myself. I challenge you to do something and do it better than you originally thought you could.
That's all I've got for now, but I know there's more spinning in your head.
What did I forget? What do you think will be regretted in the not so distant future? Do tell, I know you've got it in you...