Here is how I painted my very first Cadian. He was done as part of a general edge highlighting video, which can be found on my YouTube channel.

Regimental Khaki

1. Basecoat with Zandri Dust .
2. Wash with "Marine Juice" this is a mix of 3 parts, Reikland Fleshshade , 3 parts Army Painter Dark Tone and 4 parts Lahmian Medium . You could just use Agrax Earthshade , if you wanted.
3. Add chunky highlights of Zandri Dust and Karak Stone mixed 1:1.
4. Do a fine edge highlight of everything with a mix of Karak Stone and Screaming Skull .
5. Selectively highlight everything with Screaming Skull .
6. Add selective specular highlights of Wraithbone to points and places where highlights meet.

I used to wash the fatigues with Agrax Earthshade on my earlier models, but have moved over to "Marine Juice" as I find using it easier and prefer the result. In fact, "Marine Juice" retains so much of the base colour, you can probably just skip the Zandri Dust and Karak Stone highlight, if you wanted to save time.

Green Armour

1. Basecoat with Castellan Green .
2. Mix equal amounts of Castellan Green and Rhinox Hide and thin with water to a wash consistency. Now take a thin brush and recess shade the armour.
3. Now mix some Abaddon Black and add it into the Castellan Green and Rhinox Hide from the previous step. Now do a second, more selective recess shade. Making your lines as thin as possible.
4. Now make a 1:1 mix of Castellan Green and Straken Green . Use this mix to add a chunky edge highlight to the armour.
5. Now add a fine edge highlight with pure Straken Green .
6. Selectively edge highlight corners and exposed edges with Nurgling Green .
7. Now mix your Nurgling Green with an equal amount of Wraithbone and add specular highlights to corners, plus the centre of the previous stages highlights.

Black Leather

1. Basecoat with Abaddon Black .
2. Add a chunky highlight to edges with 1:1 Abaddon Black and Baharroth Blue .
3. With pure Baharroth Blue add smaller, finer highlights.
4. Selectively highlight with very small highlights of Blue Horror .
5. Finally mix the Blue Horror 1:1 with White Scar and add specular highlights to select areas.

Caucasian Skin

1. Basecoat with pure Cadian Fleshtone .
2. Now, just slap some Reikland Fleshshade over the skin.
3. Darken your Doombull Brown with some Abaddon Black and darken the area just around the eyeball on the face, framing the eye.
4. Shade under the eye gently with a 1:1 mix of Cadian Fleshtone and Thunderhawk Blue .
5. Reestablish the basecoat Cadian Fleshtone on raised/exposed areas, in preparation for highlights.
6. Gradually add Wraithbone to the mix, highlighting smaller and smaller areas. You should eventually be adding highlights of pure Wraithbone .
7. Bonus: If you want to add stubble. A glaze of Dawnstone works very well.

Dark Brown Leather

1. Basecoat the leather area with Rhinox Hide .
2. Glaze most of the leather with thinned Mournfang Brown . Use quite a small brush and drag towards edges in rough lines. This should create some extra texture.
3. Add a chunky edge highlight of Skrag Brown to all edges.
4. Highlight everything again, this time with a fine line of Skrag Brown and Ushabti Bone mixed 1:1. This is a good mix to throw in occasional fine lines as scratches
5. With pure Ushabti Bone , selectively highlight corners and exposed edges of the leather. Put a dot of this colour where the additional scratched above meet edges too.
6. Add a little pure white (like Dead White ) to your Ushabti Bone and add dot highlights to corners.

Steel

1. Basecoat with Leadbelcher .
2. Wash with Nuln Oil .
3. Add highlights with Ironbreaker .
4. Now selectively highlight with Vallejo Model Air Silver RLM01 Metallic .
5. If you want to add some shading and gradients on blades, use glazes of Basilicanum Grey and add some Abaddon Black for smaller darker areas. These are best applied before you start highlighting.

Gold Details

1. Basecoat with a 1:1 mix of Retributor Armour and Liberator Gold .
2. Wash with Reikland Fleshshade .
3. In particularly deep points, like eye sockets on skulls, I like to add additional shading. Generally, I use a mix of Rhinox Hide and a touch of black, and water the mix down quite a lot.
4. If needed, re-establish the basecoat on areas that need it. Then start adding Silver RLM01 Metallic to the base mix and add some highlights.
5. Add pure Silver RLM01 Metallic in dtos to areas that would really catch the light.

Black Weapon Casing

1. Basecoat with Abaddon Black .
2. Edge highlight everything with a thick line of Dark Reaper .
3. Highlight everything again, this time with a thin line of Thunderhawk Blue . This colour is a good place to put in some scratches too.
4. With Fenrisian Grey , selectively highlight upward facing edges, corners and prominent edges. Stick primarily to edges where the light would hit and always drag your brush towards the brightest point. If you added scratches previously, reinforce them with a smaller, thinner line underneath.
5. Finally, edge add small highlights to the centre of the previous highlights and corners with Blue Horror . Try to make them very small, dots if at all possible.