If you are walking on any hard surfaces other than ice, ALWAYS WEAR ICE SKATE GUARDS. This is crucial for preventing the dulling, denting and scratching of your skates, which could increase probability of rusting.
Wipe your ice skates and dry them before putting on the skate guards to further decrease the chance of rust formation.
Keep the ice skate guards on when placing your skates in your bag. This will protect the blades as well as your other belongings.