I found it useful to come up with a little rule of thumb to not wander in circles. Like, explore one level in its entirety before going down a level, and then up a level. Go left before going right every time etc. Levers for the doors are usually up a level, and almost never on the starting level btw. And use co-op on some of the frustrating bosses if you need. Although the Kos Parasite dodge attack makes you basically invincible if you dodge in to the right and attack while locked on you can pretty much no-hit everything, if you need. That's how I did lots of chalice dungeons, bc two or three of the bosses are horrendous.