Dave is one of the zombies from my custom figure line "The Restless."
I took a regular 12 inch GI Joe style figure and mangled him up a great deal with a Dremmel tool (When you do this, think of how human teeth would mangle flesh... it keeps things in perspective). I sculpted new hands and a head for him from Sculpey. His left arm is a total new sculpt from the wound down. It hangs from a strip of muscle made from vinyl. The protruding bone from his arm is the runner (that frame that model parts are attached to) from a model kit carved to look like bone. The bone of his fingers were made the same way. His clothes (just regular Joe or similar sized fashion doll clothes) were distressed in the places where his Dremmel "injuries" were. I painted him and added hair from teddy bear fur to his head.
When you paint blood, remember that blood is rarely flat red. There are all kinds of colors to blood, and different wounds from different parts of the body bleed differently. When you paint your zombies, remember that they are usually walking around and the blood should look like it's running down them from top to bottom. The more wounded the zombie is, the more blood he'll be covered in. Soak those clothes too... when you bleed it seeps into any clothing you wear. The key to making really convincing gore is gloss finish. It makes the blood look wet and the wounds look fresh. Use it liberally on exposed muscle and interior organs, and you'll make your friends gag every time!!!
If you plan on making zombies collect extensive autopsy and crime scene photographs-- you can never have enough reference pictures for anything you are trying to duplicate!!!