I used local referrals to choose my tattoo artist. Note: he was in high demand so I had to wait 8 months after the initial meeting before I could get an appointment in his chair.
In the initial meeting, I brought him a general outline design and some pics of things I wanted included and we sat down together and figured out the placement, size, etc. of all the elements. (He didn't trace the pics, he used them as inspiration when drawing it himself.)