This is my take on a scheme for the Agents of the Inquisition.

The main colours are silver, gold, and bronze with green and red elements.

General Information:

My general method is to lay down all the base colours for the model, then do all the shading in the recesses before moving on to the highlights.

I don't own an airbrush, so the recipe will mainly consist of brush on paints.

Priming:

I find the metallic sprays from GW tend to be a little on the transparent side, so an initial undercoat helps.

1. Prime the model lightly with Chaos Black
2. Prime over that with Leadbelcher

Silver (Armour):

1. Drybrush over the model with Leadbelcher to even out the coverage
2. Shade the recesses with Nuln Oil
3. Drybrush upper facing surfaces with Ironbreaker
4. Lightly drybrush upper facing parts with Stormhost Silver
5. Highlight the edges with Stormhost Silver

Gold (Armour Details - Shoulder pads, Inset details):

1. Base with Retributor Armour
2. Shade the recesses with Agrax Earthshade
3. Add Seraphim Sepia into the lowest lying recesses
4. Add a slight highlight to the middle with small amounts of Auric Armour Gold
5. Highlight fine edges with Stormhost Silver

Bronze (Armour Details - Keys, Skulls, Assorted Details):

1. Base with Balthasar Gold
2. Shade the recesses with Agrax Earthshade
3. Add a highlight using a 1:1 mix of Balthasar Gold and Canoptek Alloy

Green (Details - Cloth):

1. Base with Incubi Darkness
2. Shade the recesses with Nuln Oil
3. Re-apply the Incubi Darkness on the upper facing portions of the fabric
4. Speckle on thin amounts of Kabalite Green into the middle of the Incubi Darkness and along the edges
5. Inside that, speckle Sybarite Green leaving some of the other colours showing
6. Add a final highlight by speckling Sybarite Green mixed 1:1 with White Scar

Brown (Details - Leather pouches, Weapon grips):

1. Base with Rhinox Hide
2. Shade over with Agrax Earthshade
3. Roughly highlight the middle with lines of Skrag Brown
4. Add a fine highlight of Ushabti Bone over areas of Skrag Brown

Red (Details - Gun casings, Purity seals):

1. Base with Mephiston Red
2. Shade the recesses with Agrax Earthshade
3. Highlight the edges with Wild Rider Red
4. Add a fine highlight of Fire Dragon Bright

Blue (Details - Power cables):

1. Base with Sotek Green
2. Shade the recesses with Nuln Oil
3. Highlight the middle with Temple Guard Blue
4. Add a fine highlight of Baharroth Blue

Beige (Details - Paper):

1. Base with Rakarth Flesh
2. Shade over with Agrax Earthshade
3. Roughly highlight the edges with Rakarth Flesh
4. Highlight the edges with rough lines of Pallid Wych Flesh

Unhealthy Skin:

1. Base with Rakarth Flesh
2. Apply a thinned wash of Guilliman Flesh mixed with Lahmian Medium all over
3. Layer with Rakarth Flesh
4. Apply a small amount of thinned Volupus Pink around any metal pieces
5. Glaze a small amount of Athonian Camoshade on the lower portions of the face.
6. Highlight fine edges with Pallid Wych Flesh