I created this zombie cartoon after trying to come up with a political cartoon that was dealing with the utter selfishness that was going on in Washington, D.C. amongst both political parties. After doing some “brain” storming for an idea using free word association (which is a technique I use to come up with ideas for all of my cartoons -whether political or humorous) I had the word “brain” written down among many other words and then after “drilling down” with the word “brain”, I came up with “zombies”…..and that was the impetus for coming up with this zombie cartoon.
The process I use to come up with all of my cartoons or comics is coming up with the idea first and then after an idea is formulated, I come up with cartoon sketches, and after a few of the cartoon drawings (sketches) – that are done in pencil usually, I then choose a final cartoon sketch and then tighten the sketch up with a real tight pencil drawing. After the pencil drawing is done, I then usually go to ink. For inking purposes, sometimes I use a brush and ink, which is how I usually do all of my final inkings for editorial cartoons, but when doing most of my cartoons I use a black marker that has somewhat of a flexible tip. 
Markers work great for everything – whether drawing thumbnails, or doing finished cartoon drawings they work great. In fact, I have a collection of markers that I use. My favorites are the Papermate Flair pen, the Pilot Fineliner, Pigma series of pens and a couple different sizes of the Sharpie markers. All are great for cartoon drawings, sketches and final art. Here is an excellent article on some of the pens I use for drawing.