What are some indirect and direct characterization presented by Chris's adventures and interactions with others.

Certainly everything that Chris does is indirect presentation. Every counterculture excursion he does qualifies. So, leaving his little car and just walking away tells us something. The Author tries to stay away from direct presentation. I think he attempts to explain Chris with his own experience at times.

Characters like Wayne Westerberg do comment on Chris which is a form of direct presentation. You should be able to easily find quotes on Chris in the book or on the web.