I've completed some 28mm Old Glory British Rockets. Ok, maybe they're assembled incorrectly, but they did not come with directions. I found a blog, where someone else had assembled theirs and I copied them. I have since seen an Osprey book and either Osprey or I mounted their rockets a wrong.
I sprayed them with a gray primer. The painted wood is Model Color Azure. The rockets are Model Color Black Gray. The metal bits are Model Color Gunmetal Grey. The bare wood is Model Color New Wood.
After that I squirted white glue all over the base, dipped them in sand, and let sit overnight. The next day I painted them with a black Minwax wood stain. While drying I painted the sand brown, tan, then light tan using cheap craft store paint (Apple Barrel Brown, Crafts Smart Golden Brown, and Apple Barrel Sandstone). I applied a little flock and fake grass. When that was all dry I touched up the paint job a little bit.
I would suggest to anyone else, that they paint before assembling. The underneath parts where a chore.
I love Zombies, but I can't stand assembling Wargames Factory zombies. It's funner I just found if you chop some of them up. Chopped up zombies will assist with the variation, as I don't want any duplicate zombies. I added glue gun glue for guts on one. They're unpainted, except for the blood I quickly doused on simply for fun.