I'm doing my Khorne Daemonkin army as the Skullsworn (my interpretation on one of the warbands depicted in the codex). Here's a couple of examples:
This Helbrute shows how I'm doing the majority of the mortal side of the army. The whole thing was first sprayed with Army Painter Pure Red primer. I painted the fleshy parts first, then the silver metallic parts like the Multimelta and the pistons with
GW Leadbelcher. The brass trim was done with
GW Screaming Bell base paint. Once I had the base colors down, I shaded the whole mini with
GW Agrax Earthshade. That stuff is pure talent in a pot. Anyway, I then repainted the armor with
GW Evil Sunz Scarlet. I highlighted the brass trim with
GW Hashut Copper to make it a little more shiny. I'm pretty happy with how it came out.
This Juggerlord was done a little differently since I didn't use red primer (I used black). I painted the rider's armor with
GW Mephiston Red, then the Juggernaut in
GW Khorne Red. The brass trim was done in Screaming Bell. I shaded this model with Agrax Earthshade also, as it works really well with the brass and the red, although you could probably get away with Nuln Oil as well. After the shade, I added another coat of Khorne Red to the Juggernaut, making sure to leave the recesses a little darker. I painted the rider's armor in Evil Sunz Scarlet. The brass trim was highlighted with Hashut Copper just like the Helbrute. I'm pretty happy with the results myself, although my photography skills do not do them any justice.