I'd clean it well and let it dry COMPLETELY.
Store in a cool dry place and not all piled on top of each
other.
I have a few storage bins: one for wetsuits and stuff,
one for stuff I no longer use (wanna buy it?), one for my
wife's mask, etc when she stops diving during late fall,
winter, early spring.
I dive year 'round so my gear is never stored: just hung to
dry and then packed the day before a dive.
I hung some PVC pipe from the ceiling supports and that is
what I drape my dry-dry suit or wetsuits over between dives.
It is wide enough that it does not compress the material.