Advice on getting the most out of Portland

Me and a group of friends are visiting Portland Oregon from Texas. Our first destination is Portland and I'm looking for best places to be at that you guys recommend. This be like comic book shops, ramen places, art scene, coffee shops, anything to do with illustration and nature.

The only thing I know from Portland is portlandia, the graffiti indie movie and that's about it.

Bonus if you can tell us what places to avoid this be traffic times, places to avoid. We want to respect and be wary of since it's our first time visiting. Thanks