As long as it's a "HONG NORR RACING" tramp-stamp, you're in good shape.
Whoever said "YOU'LL REGRET IT!" was dead wrong. I know dudes twice my age with tats that love them.
MY rules of thumb (they don't necessarily apply to anyone else:)
1.) Don't ever start with "I think I want I tattoo, I wonder what I should get?" I'm guessing this is how the millions of berkeleying taz's & tweety birds have gotten branded on people.
2.) Don't be a berkeleying pork-chop: i.e. Go big or go home. 15 tiny tattoos looks like there was no forethought involved, and generally silly. If you're getting a 1/4" X 1/4" peace sign on your pinky toe, why even waste the artist's time.
3.) Put a lot of thought into placement. Your back is the biggest canvas on your body. Don't waste it. Common sense pretty much applies everywhere else.
4.) Find an artist you like, and LISTEN TO HIM/HER!!! If the artist politely suggests "If I were you, I'd put it a little lower, make it a little bigger, etc." berkeleying DO IT!