OH MY GOD WOULD YOU LISTEN TO ME LATELY?!?!?!

So what would you like to take back from your youth or add on to. Say you had a time machine, and you could only go back to one moment in your life, and add or subject something. Kind of like a variable, like you were a programmer. Just one thing that you feel would enhance or change it.

I'd start but I can't think of very much to change. Probably not fail college, and add a little more common sense to young me.