To make painting the main colour of my traitor guard easier, I primed them in red. I used a Rustoleum red spray, but any similar shade will help.
Basecoat the red areas of cloth with Word Bearers Red .
Wash the cloth with Wyldwood , thinned with Contrast Medium in a 1:4 ratio. Only let the paint settle in recesses.
Now mix Word Bearers Red and Evil Sunz Scarlet 1:1. Use this paint to add a chunky edge highlight to the cloth. I drag my brush towards the edge in lots of fine lines, just add texture. If there are any raised areas that look like they would be hit by light, you can use this mix to stiple on highlights too.
Now add an equal amount of Squig Orange to the mix, so it is 1 1 1. Add a fine edge highlight to the cloth. If you stippled any highlights in the last step, do the same here, making the area smaller and less dense.
Now add a little Pallid Wych Flesh to the same mix, desaturating the colour. Use this new mix to selectively highlight prominent bits of cloth, keep the highlights small and drag the brush towards the corner. Feel free to stiple odd dots along the previously highlighted edges, making them look more textured.
Now with pure Pallid Wych Flesh , add specular highlights to extreme points. If any of the stippled edges from the last step look like they need it, feel free to add an occasional dot within them.
Chaos Tainted Skin
Basecoat with a 1:1 mix of Bloodreaver Flesh and Kislev Flesh .
Wash with Reikland Fleshshade and Lahmian Medium .
Add some Pallid Wych Flesh to your original skin mix (roughly 1 1 1) and selectively highlight raised areas of skin.
Add specular highlights of pure Pallid Wych Flesh to knuckles and other points.
Basecoat with Rhinox Hide .
Mix Rhinox Hide and Gorthor Brown 1:1. use this colour to add chunky highlights.
Now with pure Gorthor Brown add fine edge highlights.
Selectively highlight corders points and aexposed curves with Baneblade Brown .
Now mix some Pallid Wych Flesh into this Baneblade Brown and add specular dot highlights where appropriate.
Basecoat with Abaddon Black .
Drybrush the top with Eshin Grey and add chunky highlights to edges.
Add fine edge highlights of Dawnstone to edges. You can also add a few dots and scrathes within areas the drybrush caught too.
Selectively highlight corners and prominent curves with pure Administratum Grey .
Add a little pure white (I like Dead White to the Administratum Grey and pop specular highlights on corners.
Basecoat with Rakarth Flesh .
Wash with Agrax Earthshade and Lahmian Medium , mixed equally.
Add edge highlights of Rakarth Flesh and Pallid Wych Flesh mixed 1:1.
Add selective highlights of pure Pallid Wych Flesh .
Add specular highlights of a pure white, like White Scar or Vallejo Dead White .
Basecoat with Abaddon Black .
Edge highlight all the edges you can get to with Skavenblight Dinge .
Selectively highlight edges with Stormvermin Fur where light would hit.
Mix some Screaming Skull into the Stormvermin Fur and adf occasional dot highlights within the last stage, giving the impression of rough edges.
Dark Metal Armour
Basecoat with Gunmetal Grey .
Mix Duraluminum 1:1 with the remaining Gunmetal Grey and carefully drybrush the armour. The aim here being to pick out only the most exposed areas and edges.
With pure Duraluminum add fine highlights to exposed edges and corners.
Finally, add spot highlights of :chrome or Silver to relevant places.
Weathering for Metal
For rust I like to water down Mournfang Brown , Skrag Brown and Ryza Rust seperaately. I thin them to roughly a wash consistency and place them in crevaces and areas that look like rust would gather.
Additionally, painting streaks and staining with Skeleton Horde and/or :snakebite leather can make the armour look even dirtier.