My answer to the original question would be … don't bother
Maybe you could do it for the experience of feeling the sensation of being tattooed.. but it's an experience that it would do no harm to live without IMO..
Or perhaps you could get some major work done that may possibly announce an allegiance to a group of like minded inviduals.. a heavily tattooed person certainly gives the impression that they may harbour certain views about society..
But a small insignificant tattoo that you don't really want anyone to see.. could simply signify an inibility to buck a fashion trend..
EDIT: IMO
ADDITIONAL EDIT: is there any merit to theories about acupuncture type effects of being tattooed in certain areas of the body..? think chakra and chi re-alignment.. just a thought