The "you only live once" argument doesn't really make sense for permanent things. That's an argument you make for things that are fleeting, where you get one shot at it. While it may seem like you are "trying to live as someone younger" if you get a tattoo at 30, you will still have the same tattoo at 30 if you get it at 20 -- it seems just as desperate (the observer doesn't know when you got it). You also have to bear in mind that what seems like a good idea at 20 really might not seem like such a good idea years later. Which is why tattoo removal is a booming business right now. At any rate, that's neither here nor there. If you are going to get a tattoo, get one in a location that folks won't see and take issue with. Shoulderblades, chest, abdomen, ankles, legs, back all are covered in the OR and wards so you can do what you'd like there. Arms, neck, face should be kept un-inked from here on out.