I've listed Citadel and Armypainter paint for you to use. I like the Citadel washes, but you can make your own choices ofc.

Model

1. prime the model with Chaos Black
2. Paint the metal areas with Leadbelcher or Gun Metal (they are the same).
3. Wash the dark metal (like the joints, spine and fingers) with a 1:2 ratio of Black Templar and Contrast Medium
4. Wash ALL the metal with a 1:1 ratio of Nuln Oil and Lahmian Medium . This will leave a satin finish over the darker metals we just washed with blacktemplar and creates nice defenition on the lighter metals like the armour and the shoulders.
5. Basecoat the weapon and cartouche with Abaddon Black or Matt Black (they are the same).

Base

1. Add texture (sand of a paste)
2. Basecoat the ground with a very thinned down Dryad Bark or Obsidian Skin (they are the same).
3. Basecoat the stones with Rakarth Flesh (there is no Army painter equivalent)
4. Wash the stones with a 1:1 ratio of Coelia Greenshade and Lahmian Medium
5. Drybrush the whole base with :Armypainter/
6. Drybrush the stones with :Armypainter/
7. Wash the base ground with a 1:1 ration Agrax Earthshade and Lahmian Medium