When you are not wearing silver, it is best to store it dry and as airtight as possible (not so charming but very effective against oxidation is a plastic ziplock bag). When your silver turns black, you can wipe it clean with a flannel cloth, possibly with a damp cloth with a little ecological dish soap or with silver polish. Silver is a soft metal, it will not break easily (just be careful with thin welds) but will deform easily in thin places.