undercoat and base armour

1. spray or brush prime the model with Abaddon Black
2. paint all the armour with Castellan Green
3. paint a transitional layer of Death Guard Green making sure to leave some Castellan Green visable
4. lightly drybrush some Ogryn Camo over the armour to catch the edges

detailing the bits

1. Paint all rivets and decorative brass with Balthasar Gold
2. Paint weapon blades chain links and pipes using Leadbelcher
3. Mix 3 parts Rakarth Flesh with 1 part Mephiston Red to get a bruised skin base paint the mutated parts
4. paint every boil and blister Flash Gitz Yellow
5. coat any cloth Naggaroth Night
6. on any bones/horns paint Morghast Bone

grime wash

1. wash the mini with Agrax Earthshade heavily letting it pool in cervices

weathering and final highlights

1. edge highlight the sharpest bits with Ogryn Camo
2. use Nihilakh Oxide and put it on the recesses of the Balthasar Gold
3. edge highlight the tenticals with Emperor's Children
4. put a messy coat of Nurgles Rot on the tenticles
5. lightly drybrush Necron Compound over wepon teeth and blades
6. mix Thondia Brown with water till its like a watercolour wash drag lines down from the rivits and armour cracks