I did a lot of reading on PID tuning and even experimented with autotune (<--- doesn't really work).  These 2 videos were the most helpful videos  for me:

Setup adjustments on cleanflight


Using in flight adjustments. 



I used information on Oscar's Blog to make sense of everything else that wasn't explained on the video:
http://blog.oscarliang.net/understanding...rc-flight/

Another video by Oscar shows comparison between different PID settings.  


Maybe one of the pros here can add some descriptions on what to look for on the graphs.  I can pick out the obvious problems, it would be good to get some additional info from someone with more experience.

Thanks for putting together this reference. I feel like I've learned so much about PID tuning lately, but still can't seem to obtain that "locked in" feeling yet. Going to keep on truckin!

Thanks for doing this very informative ?