Base coating

1. Airbrush Molten Orange or paint a basecoat of same colour, called Molten Lava.
2. Do a zenithal highlight using airbrush with Lava Orange or paint broad highlights, i.e., more than 90 of the model, everything on the armour except recesses with Lava Orange

Shading

1. Mix Speedpaint Medium and Warrior Skin 1 to 2 or 1 to 3. Ass the mix in the deepest recesses and panel lines on the armour.