Basics:
1)Novice -> pay_fild04
2)Sword/Merch/Thief -> pay_dun00 until lv60/50
3)Knight/Blacksmith/assassin -> orcsdun01 until 80/40ish -> gef_fild14 until 99 for rebirth
High Novice-> rinse and clean from step 1-3
4)LK/WS/SinX -> AFTER orcsdun01 / gef_fild14, get yourself an ice pick in the item mall. You can gather gold for zeny in gold room. Otherwise, go hunt yourself one and head into lhz_dun02. (optional) ice_dun03 and kill ice titans.
5)
LK -> Lv200+, head into odin_tem02/03 and have equips ready to own angel / demon monsters.
WS/SinX -> Lv180+, head into thor_v01/03 and have equips resist to fire (duh), and then equip some fire damage equips.
6) Reborn to 3rd job and rinse & clean on step 4 to 5.