Full credit to Darren Latham. I took his vid, tried to make it a bit more Chaos (kept the flesh darker, added veins). Here so I can remember the steps!

Basecoats and Layers

1. Basecoat Bugman's Glow . Several thin layers.
2. Layer a 50:50 mix of Bugman's Glow and Cadian Fleshtone . Leave deepest recesses. Again, very thin layers.
3. Layer Cadian Fleshtone as before, leaving deepest recesses etc.
4. Layer a mix of Cadian Fleshtone and Kislev Flesh . Same as before (paint is quite watery).

Shading and Tones

1. Recess shade, wash consistency, with Bugman's Glow mixed with Gorthor Brown . I didn't have the brown Daz used.
2. Same again, but deeper with Mournfang Brown
3. Very fine line with Rhinox Hide on only the very deepest, like eye sockets, around joins with armour etc.
4. Back to highlight with Kislev Flesh on the most raised points, such as cheekbones, eyebrows, top of head.
5. Same again, but with Ushabti Bone .
6. Adding colour, use watered down Bugman's Glow and Khorne Red around mouth, cheeks, scars.
7. Same again, but just Khorne Red . Again, wash consistency.
8. Mix Thunderhawk Blue in to the red, for a rich purple. Run around eyes.
9. Add veins using the above mix. Only use the tip of the brush. Very thin paint.
10. Establish highlights again with Pallid Wych Flesh on very highest points.

Eyes

1. Run a mix of Rhinox Hide and Abaddon Black into the eye.
2. Paint the whites of the eyes with White Scar . I did this as a line horizontally, then tried to follow the shape, leaving some of the black edge.
3. Paint the pupil, making sure it goes top to bottom (do as a line, then thicken). Look at the head upside down to help make sure you're not doing wonky eyes!

Finishing Touches

1. On only the very highest points, a dot of White Scar can be a applied to the skin.
2. If you have the skill, or big enough eyes, you can add a dot of white to the black pupil.
3. I used Contrast Medium across all of the skin to even the finish.