1) Make holes bigger if there’s not already a clear path to the surface.
2) After you die, don’t try to grab all your stuff at once; locate first, get air, then retrieve.
3) If reasonable (i.e., not too deep), work from the surface–holes in caves are harder to get back into and have down currents that are harder to swim up through.
4) Start heading up *before* you run out of air–it’s really hard to swim while you’re drowning.

Be safe! :)