For painting miniatures, I use acrylic colours which I buy in art stores. I use different brands. I also add a medium to the colours which turns them completely matt. The medium I use is from Lascaux (Switzerland), but I know of a similar medium produced by Vallejo, as well.
For the skin colour of human miniatures, I use Naples Yellow Red as my prime component. I always start painting with the darkest shade. For that, I mixed Naples Yellow Red with a greenish dark grey. This grey consists of the prime colours blue, red and yellow. I have three different greys mixed out of the prime colours which I use for shading. Either green, red or purple stand out of the grey.
I used two shades of the skin colour before painting with pure Naples Yellow Red.
To highlight the skin, I added white to Naples Yellow Red. I painted three highlight steps.
After that, I mixed Naples Yellow Red with Cadmium Red Deep and painted the lips.
I then added loads of water to this mix, and used it for the cheeks.
For the eyes and teeth, I mixed white with a tiny bit of yellow. Pure white would not look natural.
For the pupils, I used pure black. I also added a white dot to the pupil - this adds life to the face.