This is my take on the Magma Hounds colour scheme, most recently in the 8th Ed Chaos Space Marine codex.

The main colours are red and gold.

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 of grey helps.

1. Prime the model lightly with Mechanicus Standard Grey
2. Prime over that with Retributor Armour

Gold (Shoulder Pads, Armour Trim):

I generally start with the armour trim so that any time I get paint on another piece its easy to cover later.

1. Drybrush over the model with Retributor Armour to even out the colour
2. Shade the recesses with Reikland Fleshshade
3. Highlight fine points and sharp edges with Stormhost Silver

Red (Armour Panels, Lenses):

1. Base the areas with Mephiston Red
2. Shade the recesses with Agrax Earthshade
3. Highlight the edges with Evil Sunz Scarlet
4. Add a fine highlight with Wild Rider Red
5. Highlight fine points with Fire Dragon Bright

Silver (Details - Chains, Weapons):

For grenades, replace Nuln Oil with Athonian Camoshade

1. Base with Leadbelcher
2. Shade the recesses with Nuln Oil
3. Highlight fine points and sharp edges with Stormhost Silver
4. A rust effect can be added using thinned Skrag Brown

Black (Details - Armour Ribbing, Weapon Casing):

1. Base with Abaddon Black
2. Highlight the edges with Eshin Grey
3. Highlight fine points and sharp edges with Dawnstone

Grey (Details - Wraps, Tabard, Scanner Case):

1. Base with Mechanicus Standard Grey
2. Shade the recesses with Nuln Oil
3. Highlight the edges with Dawnstone
4. Highlight fine points and sharp edges with Administratum Grey

Brown (Details - Leather Pouches):

1. Base with Rhinox Hide
2. Shade the recesses with Agrax Earthshade
3. Roughly highlight the edges with Skrag Brown
4. Add a fine highlight of Ushabti Bone

Blue (Details - Plasma):

1. Base with Sotek Green
2. Shade the recesses with Drakenhof Nightshade
3. Highlight the edges with Temple Guard Blue
4. Highlight fine points with Baharroth Blue

Green (Details - Scanner Screen):

1. Base with Caliban Green
2. Shade the recesses with Nuln Oil
3. Add lines of Warpstone Glow
4. Add fine points of Moot Green