Proper PID tuning?

From what I understand, tuning guide WiKi is super outdated. Can someone point me to up-to-date method?

Actually it is not that outdated. I just used the wiki to tune a 450 size heli using DX8G2. I used the knob at CH6 to set the tuning range. However I do agree that it needs update in certain areas. Perhaps we can put our inputs here which ultimately will transform into a proper documentation.