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I was contacted by Bill to see if I would be interested in doing four character figures, along with an article on how I painted them. The only specifics regarding colours and how he wanted the figures painted was "make them look great," which I hope I have achieved.
In the articles, I mention mixing paints - this is very hard to describe, as I don't use a specific method or ratio, but I will give it a go:
Always start mixing with the lightest colour first, adding the darker colour to it. I add water to the mix by dipping the same brush in the water pot, and wiping off the excess. After the mix looks about right, try it on the figure and let it dry - if it is the wrong shade, you can simply add a little of either colour to the mix until you get it right. Adding water gives a nice blend inbetween shades, and also keeps it fluid if you are doing batches - but be careful not to get any bubbles on the figure.
I mainly use the Foundry painting system (with a few mixes for inbetween shades) and GW paints, as they give excellent coverage.