When I went, I just walked in and gave them my design idea. It took about 2 hours for them to draw and then I came back and got the tattoo all in one day.
Depends on the size, detail, and availability of the artist. It's always best to make an appointment, unless it's something relatively small. I worked with all those guys, and they'll take care of you
Your best bet is to talk with them, each artist is different in their own way. But all are extremely professional and willing to work with your ideas. I've gotten 5 good size tattoos from one of the artists there and he works with my ideas all the time. I've chosen to stick with him for all mine from this point on I loved the tattoos so much. But yeah go in or call...best way to see what can be done.
Normally an hour or two if small or simple.... depending on the size and if you like the first sketch... or if alterations need to be made is in the end up to you and the artist and if he is busy.
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