Just before making a tattoo, ask what kind of instruments and paints do they use.
The most trustful and famous brands of tattoo machines are Huck Spaulding (USA), Micky Sharps (England), Biotek (Italy), Jet France(France).
The second vital thing is paint. The indicator of paint’s quality is its price). But remember that you never can be fully sure that the quality is good! Nevertheless, there are several most popular brands of paint: Micky Sharpz (England), Precision and Time (USA), Biotek (Italy), Jet France (France). As you see they are also tattoo machines producers.
After you have checked the devices which would be used, be sure that a master shaved hair on a piece of a body and sterile it with methanol. When the tattoo is ready it should be covered with vaseline.