The first setup step is securing your armcuff in the proper location for you, and adjusting to the optimal shaft length...for you.
I mainly detect parks, schools & sportsfield areas, curbstrips, and yards.
So...
I usually run Park2, with 50 tones. Always noise cancel first, then find clean ground to ground balance.
MULTI-FREQUENCY is preferred, unless I need to switch for EMI or other reasons.
SENSITIVITY: EMI can cause some level of chatter in most places, so I set sensitivity to just below annoying chatter levels. Sometimes I lower Sens. to work near metal fences, playground equip., etc.
VOLUME usually at 22-23, so I can bump it to 25 if it's noisy around me.
No THRESHOLD sound.
I leave IRON BIAS on the low side, because it's a compromise, and I opt to go low. (I think 2 to 4, but it's fuzzy) So far, I haven't noticed much difference in FE, F2 bias settings. I'm not well versed in iron bias settings.
RECOVERY SPEED is usually around 5 to 7. If the ground is especially "clean", and I want to search for deepest coins, I will lower it to maybe 3, and sweep slowly. If the ground is trashy, I set R-speed to 7, but would consider going all the way to 9 if I want to do some quick clad sweeping amongst the pulltabs.
I ACCEPT everything, and REJECT nothing, except the iron (o to -9). I use the horseshoe button to listen for iron at times, but don't leave it on much.
I prefer to use the headphones plugged into the WM-08 module. That thing pairs up quickly and perfectly every time.
I am certainly not at expert level with this stuff. Much of it was trial and error, and picking up tips here and there. Actually that's still the case.
It seems everyone sets up a little differently, but many different setups seem to work well for different people, ground conditions, hunting styles, etc.