you should be good with the OEM settings unless you do some aggressive riding
at the moment mine is set to the softest settings, and no preload. the only thing I would change for the street is preload, but compression and rebound damping you can usually leave alone for now. (But if your forks are bottoming out on big bumps or while braking hard, you must definitely add some compression damping. a zip tie on the fork leg will tell you how far the fork travel is while riding).
also, if you buy a bike used, check to see if the previous owner changed any of the settings. your owner’s manual will usually tell you what the OEM settings are. (when I bought my R6, the prev owner had set the suspension to the stiffest settings, and the bike felt a million times more comfortable after I softened everything up).