Not to be an alarmist, but...okay, well maybe I do mean to be an alarmist...if there's something you want to do or say, you should do it or say it already. Except for unnecessary plastic surgery; do not have unnecessary plastic surgery.
You want to square dance? Then square dance! Not that I understand why you would choose to do that, but still: square dance!
You want to re-read the entire series of Game of Thrones books? Do it! I totally understand why you would choose to do that!
You want to tell someone you haven't seen or talked to in 5 years that you love them deeply and for all time until every river runs dry? Go ahead! At your own risk, that is. If you can't think of another option, that is. If your spouse won't be upset, that is. I can sort of understand why you would choose to do that!
Cut your hair off! Eat Jell-O in its crystallized form! Break into song at the mall while simultaneously eating at, I don't know, Panda Express!
Write the book, paint the canvas, print the t-shirt.
Learn to play the violin! I guess.
Master five yo-yo tricks! Take photos without using an Instagram filter! Toss your iPhone off a bridge!
Time is a finite resource, that's what I'm trying to say. It's slipping away from you even as I type, even as you read. The people you love dissolve into the ether, the person you were yesterday doesn't exist anymore and, per the great poet, the center cannot hold. I repeat: the center cannot hold.
Do the things already.