For these tutorials I will be using the Warpaints range of from Army Painter. This is primarily for simplicity as the colours are quite generic so whatever range you use there should be a similar colour. They are also high quality paints and well worth buying.
Natural umber pigment - vallejo
Hair - matt black
Skin - wolf grey
Red cloth - pure red
Yellow cloth - daemonic yellow
Using white and black I sketched the lights and darks onto the metal skin.
I created two intermediate mixes of with the white and black with wolf grey. Starting with the light mix I painted a thin layer over the boundary of white and black to blur the transition. I used a slight sweeping motion with the tip of the brush only. The same was done with the dark mix.
I repeated the previous step 3-4 times adding more white and black to my mixes to increase the contrast. It's important to have only a small amount of paint on the brush as this will application easier to control and reduce the chance of unsightly brushstrokes.
I painted the lines on the skin with black. Again using a small amount of diluted paint on the very tip will make this process a lot easier.
All of the edges were given a highlight of white. This is a tricky step as white paint doesn't typically behave like other colours and can be quite grainy when diluted. But it does make a big difference to the final result and is worth taking the time to do.
To finish painting the skin I used all of the previous steps to correct any mistakes or clean the transitions.
The shading for the red was started with a mix of pure red and chaotic red. This was painted in several thin layers to all of the recesses and downward facing surfaces.
The first highlight was a mix of pure red and barbarian flesh and this was painted to folds and most prominent surfaces.
Further highlighting and shading was done by adding more barbarian flesh and chaotic red to the appropriate mix.
To finish the red I added a small amount of white and black to pick out the brightest and darkest points.
The yellow was painted in the same way as the red. The initial highlighting and shading was done with mixes of base colour plus skeleton bone and desert yellow.
The final highlight to the yellow was done with a mix of white and skeleton bone. The shading was finished with diluted fur brown.
The hair and belt buckle were painted with mixes of black and white. The base was given a wash of soft tone and natural umber pigment from vallejo. Blue wash was used to add shading to the rocks.
The finished model