trial and error.
learn by observation is about the only thing i can say.
the big driver goes from 291 listed to 312. But it really averages in at around 325 with a crosswind. (with my golf balls)
iron spin starts to take yardage off the golf ball so either have to adjust yardages or adjust the amount of spin you add.
driver and 3W distance are the most useful (IMO)
Any putting stat is hard to actually quantify. The numbers change but to be honest i don't think they actually have any actual effect on how many makes or misses i have.
Sandpower. I have no need for more power
Wedge distance- i like my wedge distances just fine.
iron distance- changes all my irons and puts a big gap between 9iron and PW...
So while not horrible it's not something i like.
anything hybrid is only useful for people below 75 and still iffy even then.
rough power sometimes handy but it changes numbers.. situationally beneficial.
Brush power- rarely even needed except for a few CTTH shots.
so to sum up... SE hat... MAX shirt.. everything else is fairly worthless to problematical except maybe 3W spin. so the rest of the slots usually go to coin bonuses.