Inking or coloring the tattoo can easy be split up in 2 categories, Lining and shading. This is because the machines you use is different, and the skill set is quite different. Lining and lineart dont necessary be made with black ink and is often made with colors as well.
Lining / Line art
This is usually the first step in most tattoos ( Except for realistic where some artist shade the contours of the design so you dont get any visible line art ) But for most of the ceases everything start with you putting the stencil paper on the skin you want to tattoo and then trace the line art with a liner machine “Liner”. This is because the lines needs to be very solid and contain big amounts of colors , and with the lining machine is build in a way that makes the distance shorter for the armature bar to travel and this in turn make the machine cycle (up and down movement) much faster compared to a shading machine.
Remember also that you need have a stronger machine if you lining big lines or areas with the big needles size 16 and more you should consider using a 12 volt machine to deal with the heavy resistance from the needles.
Another advice is to avoid using the smallest needles in the beginning, the RL01-RL04 needles is very hard to deal with and mistakes is easy and very obvious to spot.
Shading / Coloring:
This is the part when you either follow the line art and fill it with colors as the Old and New schools tattoos where a fewer number of colors are normal used.
Or you making a realistic tattoo and shading out the outlines and how its going to look like, or maybe you still following a line art but decided to use different shades and nuances of the same colors to make it more alive.
For this we advice you to use a Shader machine “Shader”. Their distance between contact screw and armature bar is longer so the machine work a little less aggressive than a Liner.
Always remember that shading does the most damage to the skin so try to avoid going back and working in the same skin area that you previously finished .