My process...abbreviated

I was asked recently about my process, and every artist does it differently, but this is how I come up with a character.  Most of the time, you have a style guide, sometimes even the work of a previous character designer to go off of.  Other times you  only have a sentence!  In this case, since this is a personal project, I like to come up with a little back story that helps me visualize and "get to know" my character.  In this case, Patches is a working clown and also a single dad of a very precocious little boy.
I almost always start off with heads and torsos.  I create a variety of head shapes (imagine two more sheets of these) then choose one that really speaks to me and pull the character out of it.  I do this by drawing over it and making more specific choices about the way he'll look, and in my mind, I'm deciding how his face will move, any characteristics that will make him unique.  Then I'll do further tweaks when I move the character to a full body.  Now all this takes place before expressions, turn-arounds, etc.  This is just the exploratory phase, but I hope you like it!