All cases - Tattoos are almost always a one shot deal. Make sure that you are positive that what you are putting on your body,you are going to be happy with. In many cases they can be a real eye sore and can really turn a lot of people off. On the other hand some tattoos can be vary cool and beautiful, and like a work of art. This is the reason you want to be very careful on what you put on your body. Like my grandma she had lips on her tits and now she is kissing her own butt. :)

Things to consider,
One- Choose a tattoo that you think you would really like FOR THE LONG TERM. Picking the wrong one can be devastating. If you get a tattoo that you can't live without right now, think of the future. You may change or mind later in life.

Two- Choose a tattoo that reflects your personality. Don't get one just to please someone else. Like the guy who gets the name of his girl on his arm thinking that they will stay together forever, and now is stuck trying to find find someone else with the same after they broke up.

Three- Don't choose a tattoo that is just a fad or something that is in style. Fads don't last long and rarely come back.

Four- Try not to get a tattoo that is up-seen or that will upset people. That person that you piss off might just be your boss some day.

Five- Choose a tattoo that has not only the look you want, but one that has meaning, and not one that just has a cool design.

Remember getting a tattoo when you are 3 sheets to the wind is never a good idea. You should always be in the right state of mind. Be careful, be honest with your self, and take your time when picking what you want to put on your body.