I figured everyone has pretty much seen my basic process, so Im going to do something a little more specific this time. Ill be focusing on the creation of the zombie head from my last design. I have never written a tutorial before, so let me know if I suck! Haha.
If a few folks find it interesting/helpful Ill make it the first part in a series. Well see.

I will assume that you have a basic knowledge of figure drawing, and that you are capable of drawing a skull for this. If you cant do that much, theres plenty of sweet books out there to get you up to speed.
Anyway.. Here goes:
Step one is simply to start the basic outline of a head. I think everyone has done this several thousand times:

Step two is to flesh out a face. I did this very quickly because the face looking well isnt important. Its just for positioning and proportion.
Also, my tutorial writing time and my drinking time seem to have overlapped. You will have to excuse me. Haha.

This is where my zombie head will stray from most zombie heads. I actually draw a quick face to use as the building blocks for a skull. In my brief experience as an illustrator I have found that drawing the face first helps my skull quite a bit.
I draw my skull by basically tracing some of the shape of the head, pretty simple. Faces sit on top of skulls, so this part is easy. If youve ever drawn a skull before, youre there.

So, now that we have a skull, we are going to build on top of it what our zombie is made of. I didnt want a fresh zombie, I wanted a guy who had been through the ringer. He is mostly composed of muscle with a few flaps of skin here and there. Hopefully you can appreciate that.
What we do now is to draw a very basic muscle structure over the face. I have simplified the structure here for the sake of time, but I think youll see the correlation between this and my design.
This is one of those areas where style is important. You will need to strike a balance between being technically correct, and being aesthetically pleasing. Mostly I lean towards making it look cool. This is also a place where you will be explaining volume largely. It will compliment your shading technique in making the head look three dimensional. This is what I came up with:

I think its important to note that I have also taken a bit of consideration into making the muscle hold a bit of an expression. What good is a face if not expressive?
I have added a bit of shading, and drawn a few arrows to denote a general flow of the lines, and the muscle tension that defines the facial expression. Basically this simple bit of detail makes the difference between a bland expression, and a hostile zombie.

The reason that I shade it in the sketch phase is that your line weight should reflect shading in the inking phase of your design. If you havent figured it out before-hand it makes a mess of things. I skipped this step to save time in my design, and I think it shows.
Once the design is inked, with shading and general shape explanation taken into account I have come to this:

And without the sketch:

This will have you most of the way towards a design that looks like such:
I have added a few contrasting pieces of muscle for effect in the first version. Also, you might note that I refine my initial sketch a bit in each step. Every time I zoom out I take a good hard look at the basic picture and try to figure out whats wrong with it.
So thats the secret sauce in my zombie face. Im new to this so if theres any questions or comments, please feel free to help me make this better!
I plan on doing a coloring/shading tutorial very soon, but now its time for me to get a bit of sleep. I hope you find this useful.
