Using Corel Draw, I started with an EPS file of robot (available from here
for your own experimentation), and simplified it dramatically.
I then split the image into three sections for stenciling purposes - an outline of Robot as a whole, a background to create the "greasepaint" stripe, and the details of Robot's body.
That took only a couple of minutes to type, but took a couple of hours to actually do
(I have attached several versions of the file to this step, so that you can create or modify your own stencils as you wish.)