There are just as many methods for creating different variations
for shading in tattoo as there are ways to tune a tattoo machine.
Ultimately it is up to the tattoo artist’s preference. This text will
cover a few of the commonly accepted practices for mixing up
the shading inks. Some artists that do mostly color work will
have large bottles of pre-mixed shading ink set up, while some
artists who do a lot of grey work will still prefer to mix their pigments
in the ink-caps prior to completing the tattoo.