That kind of depends on the tattoo artist. Some will work off of a a template that is either stamped on the skin (like a temporary tattoo) or will draw something for reference. Others will freehand a design. I would imagine this guy with this design at least plotted the stars in advance.

I don't recall if I had to sign a waiver before my tattoo was done... probably did. But then again in the case of this little hooplehead, she had this done in another country... who knows what their laws are like.