Clean, dry, lubricate -- you're good to go. Soak in WD-40 is probably over-kill, but it can't hurt. Hair dryer gets at the moisture, heater vents.
Bags and cases are going to soak up water. Depending what you have, you can toss them in a dryer. If it's not dryer friendly, spread open on a rack w/ good ventilation. I have forced air heat in the house and spread my wet garments (Harley rider) over chairs in front of the heat vents.
Rust happens when stuff gets wet and doesn't get dried out. Warm, dry place with decent ventilation does what needs to be done.