I just came across some old photos I took of various German armoured SdKfz. I've built over the years and thought I'd share:
Pzkpfw. V Panther Ausf. A- winter camouflage
Pzkpfw. VI Tiger Ausf. E- winter camouflage
Sdkfz. 164 Hornisse/ Nashorn- winter camouflage
Sdkfz. 167 Sturmgeschütz IV- summer camouflage
Zimmerit- the Panther came with this anti-magnetic mine coating moulded in (so not terribly good), but I added it using putty to the Sturmgeschütz myself- making it broken and such to show field damage.
Schürten- in virtually ever photo I've ever seen of a vehicle in the field, at least one of these standoff plates is missing, so I cut off a few on the Panther and Sturmgeschütz.
Snow- obviously in the field snow gets stuck in tracks and in various other places, so a strategic application of white putty, allowed to begin drying then pushed about to 'crumble' makes some decent caked snow.
Whitewash- since winter camouflage was applied over the usual summer paint, I did the same: painting the models first with RAL7028 Dunkelgelb, then over nearly drybrushing with flat white, purposely making it messy and avoiding markings; Dirt (Sturmgeschütz)- just dry brushing with flat medium light brown paint.
Soot- carbon paper provides actual soot, so rubbing a bit on fingers and touching the model in various places, rubbing it with clean fingers and cotton swabs and voila- a dirty vehicle (it's particularly good for gun muzzles).