I usually try to paint a test model before I start working on a large unit, especially since I have such trouble figuring out what paint scheme I want to use. For the orcs, all I knew was that I wanted them to look like they've been wandering the Badlands for a long while; their clothes have long ago lost their color from the weather and the wind. Yet I still wanted to include a dash of red since I've done that with all the units to tie them together somewhat, so I painted the motif on the shields red, which turned out to create a pretty good contrast to the bleached and muted color of their tunics (unfortunately, the flash messed up the red color in the picture). I'm not very happy with the weapon as of now, I'll probably add more rust to the finished unit.
Anyway, the color scheme for anyone interested is as follows:
Skin: BC Orkhide Shade, HL Snot Green, HL Goblin Green
Tunic: BC Dheneb Stone, W Devlan Mud, HL Dheneb Stone
Wood: BC Scorched Brown, HL Bestial Brown, HL Snakebite Leather
Leather: BC Calthan Brown, W Devlan Mud, HL Calthan Brown / BC Scorched Brown, HL Bestial Brown
Straps: BC Bestial Brown, HL Bubonic Brown, W Devlan Mud
Motif: BC Mechrite Red, W Baal Red, HL 50/50 Mechrite Red/Blood Red