Well, I usually stock up on healing items, level up my characters 3-5 levels on regular enemies, and check my recent loot and local weapon/armor stores for equipment upgrades before heading to the next segment of the adventure (acquiring however much money I need to get said equipment and supplies). This almost always works.
As for my fighting style, I usually don't waste time with stat boosters or stat drainers (I see those as ways of working around bad equipment and being underleveled if you want to struggle through unprepared, which they usually turn out to be in most games). I go for raw offensive power, preferably high-level spells and good weapons. Basically, I just try to dispatch the enemy as quickly as possible. I also usually just focus on healing and/or reviving my characters if the damage gets too bad, rather than trying to prevent damage, which is usually futile.