Curses can be addressed by: 1) blessing everything that matters before you start your ascension 2) carrying inventory in an oilskin sack (which will work fine while cursed, and protect items inside it from being cursed) 3) carrying holy water and/or scrolls of remove curse 4) knowing the remove curse spell 5) certain Artifacts and armor will reduce the effect of curses on your inventory 6) carrying a lot of lightweight junk as a curse "buffer" so that curses will have a lower chance of hitting something critical 7) wielding Magicbane, that blocks 95% of curses.

A lot of this is really just, as mentioned, time spent on planning and execution.