A few things to think about before you even start. Where does light hit him or at least where does the darkest shadows fall. Turn the lights in the room down and use a directional light. Move it around and watch how the shadows fall. I started doing this a few years back and it really has helped me get a more realistic look (in my opinion).
I also don't use the extreme highlights very much unless I really want that area to be noticed. Also, think about what material you are painting and why it will be highlighted. Is it fabric that is being worn down or stretched? I'd usually mix with pink or white to show the wear. If it's a hard sheen I'll go with an orange or yellow unless it's a pure sheen and then it would just be a pure white highlight.
But now .. onto the actual how to ..
4) Next we move onto blending the mid layer color. I use Scab Red or Gory Red (Red Gore can also work). Now you start working in between and blend the shadows into the blood red. I use 40 to 60 paint to water, This is where it starts to come together.
5) Now go back with Blood Red and blend out to the edges.You want to be clean on these layers but again you are going light with 50/50. Apply enough layers so you don't see any streaking.
6) Now I go back with the black to finish it off. Hitting all the darkest areas and blending in the Shadow and Scab (most of the time I will then go in with black ink to create any hard line shadows i think should be there, I didn't do that here). That will give you a good looking mini with only a few colors. Like I said this is pretty basic and if I was really going to go farther I'd keep blending more until all the areas were perfect and smooth. It really just depends on how much time and how good you want it to look. I already had him based red but all the blending steps only took me about an hour (including adding the bone and some shading on it as well).
I hope that helps and makes sense. It's a pretty simple how to blend with only a couple of colors. If you don't want it to look as dark use less black wash. If you want it to be brighter or love the extreme highlights you can add that on too. But, I wouldn't go overboard with the X highlights and the extra shadow. Most of the surfaces are pretty small and a blend from super dark to super light can give a unusual look.