Phil McAndrew offers up solid advice for young cartoonists and illustrators. From my own experience, every word is true, but especially this:
I’ve tried many different methods of self promotion. I’ve sent out postcards in the mail, I’ve tried shmoozing at conventions, I’ve sent cold emails and have considered cold calling art directors (I’m still considering it). The most effective thing I’ve done has actually been the simplest: Draw awesome stuff and put it on the internet. Do this for a while and good things will happen.