I recently started the SSU for dustwarfare (and won the world championships, report to follow). And started my army with a good ol' faykeli squad.
I started off by airbrushing the pants a mix of VMA meiden stone and sand, and going progressively more sand heavy for high lights.
I then started adding shadows by glazing a dark grey into the shaded areas.
I then painted all the rubber parts black and metallics with a mix of VMA gun metal and black.
Finishing up, i painted the ruck sack with GW khemir brown and shaded with dark grey and highlighted with 50/50 khemri brown and bone white then 25/75. (Ruck sack not pictured).
The rubber parts were highlighted with:
VMA light grey then VMA white.
The metal parts were highlighted with VMA chrome, and shaded with VMA black. Then i used black weathering pigments to add some scratches/damage.
The eye lenses were painted VMA light grey 25/75 VMA white, then glazed with VMA light sky blue. Then gloss varnished for effect.
I finished by going back over the hammer and sickle with white.