Melissa is one of the zombies from my custom figure line "The Restless."
I took a Gymnast Barbie and mangled her 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 a new left hand and a head for her from Sculpey.
When I sculpt zombie heads, I always start with a skull. I do it for two main reasons: it keeps the look of the facial features correct, and it helps you make the wounds look even better in the long run. I layer the muscle up from the skull and cook the sculpt again with each layer. I add the eyes before I add the skin and give the whole head another cooking. The final layer, the skin is made by rolling out the Sculpey with a rolling pin and laying it over the sculpted skull and muscle tissue. This allows me to make the skin look paper thin and to actually have the muscle tissue show up in the final sculpt. You'll need to trim out the eye holes and the hole for the mouth and it gives you an opportunity to decide at this stage what surface damage you want to show up on your zombie. I tap a toothbrush on the uncooked skin to give it a light stippled effect that mimicks pores. Don't go overboard with it, just a light, random application of taps will make a world of difference. When the zombie looks sufficiently gnarly, I throw it in the oven for a final cooking.
Her right arm was cut off mid-forearm and two pieces of runner from a model kit (the frame that model parts are attached to) carved to look like bone were inserted into a hole I dremmeled into the forearm. Her clothes from a Queen Amidalla fashion doll were distressed in the places where her Dremmel "injuries" were. I painted her and added hair from the Gymnast Barbie to her 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!!!
I do go on... but I hope it helps anyone who wants to make gory ghouls!!!