How long should I wait before getting a tattoo?

really it's upto you. I wanted one on my 18th and had chosen my design. I didn't get it and changed my idea again and I then went back and forth with those two ideas and now I've finally made a decision. i still haven't got it done yet at 24 because i don't want it to be rushed. i jotted down the design and will check back if I still like it in a few months...