While trying to find out how to make a character sympathetic, I found a few good more character-building goodies.
Inner Dialogue is vital. K. M. Weiland has 5 Ways to Write Character Thoughts Worth More Than a Penny.
Beth Hill says The Psychology of Character shows us that every time a character makes a choice, he’s revealing who he is.
What do Frodo and the evolved Superman have in common? You can relate to both of them. How to Make a Great Leading Character by Seth Frederiksen.