Haunt at Great Oak

Before going any further into making a zombie walker, you should definitely check out these four videos by Stiltbeast Studios on YouTube, since these have techiques and ideas that are used for the zombies...
Head
Hands
Eyes
Body

Materials
Loctite foam sealant - Required
Styrofoam wig head - Optional
Spray bottle - Required
Rubber gloves - Required
Paint brush(es) - Required
Acrylic paints - Required
Heat gun - Required
1/2 inch PVC Pipe - Optional
Round glass cabochons - Required
Pool noodles - Required
Wire ties - Required
Rebar - Optional
Hot glue gun - Required
Rotary tool - Optional

Cover a styrofoam wig head, or similar type of shape, with plastic wrap, a couple of layers is required to prevent sticking and/or damage to the wig head. Spray the plastic wrap with water. Spray Loctite foam sealant on the head, leaving gaps between the piped strips of foam sealant, as well as the neck area. Set a timer for three minutes and spray more water on top of the spray foam. Once the timer is complete, using hands that are damp, begin checking the foam for stickiness and the ability to be molded. As soon as the foam sealant isn't sticky to the touch and you are able to work with it, begin shaping into a complete head, including eye sockets, nose, ears, mouth, chin and neck. While you are working with it you may notice that it is starting to stiffen, which means that it is time to remove it from the wig head, or whatever was used, otherwise it will require that you cut the foam sealant in order to remove it.

While waiting for the head to set, so you will be able to work with it, you spray water into a couple of rubber gloves and then fill them with foam sealant. You will need to check them after a few minutes to determine if they are starting to set, so you will be able to shape them into your desired position.

Once the head has hardened, you can use a rotary tool, razor blade or anything else to better refine the head into what you would like the zombie's skin to be. For example, you will want to cut out where the eyes will be placed, the ears and nostrils might need to be enhanced or taken in a bit, etc.

Paint the head and hands using acrylic paints to give them the appearance that you desire. It is recommended to do a base coat of a skin tone, allow that to dry, and then proceed with layering all of the different colors individually until you have reached the top coat of paint. Using a spray bottle on wet paint allows you to create a drip effect, if desired.

Paint two cabochons to give them the appearance of being eyes. Please see the video from Stiltbeast Studios on YouTube for how to paint an eye. Once the paint on the eyes has dried, you can use a hot glue gun to attach them on the inside of the head in the eye sockets.

Create a pool noodle body, Stiltbeast Studios YouTube video. Attach the head to the body using wire ties. You can also use wire ties to help strengthen any point(s) on the body. Apply hot glue to PVC pipe and insert one into the bottom of each pool noodle leg. Apply hot glue to the body side of the hands, you might need to make it more flat beforehand, and adhere them to the arms.

You can use any clothes you would like to dress them up. The rebar is used to make them stand on their own in your yard.