A great tip to make your costume jewelry look its best as long as possible is to clean them after each use and keep them dry It might seem like a hassle after a long day, but it can make a huge difference in the way it looks and shines. There’s always the possibility that you got perfumes, lotion, oil from your skin on your jewelry while you wore it, so don’t put it away before you get the chance to clean it or at least wipe it down with a soft cloth.
Protect the plating of your jewelry by removing it when washing dishes, exercising, cleaning, washing your hands, doing laundry, going swimming (chlorinated and salt water can react with the metals).
Avoid cleaners that contain acid, vinegar or ammonia and some jewelry cleaners, as they can damage your jewelry. Alcohol wipes can be ok from time to time to sanitize the back of earrings. Also, make sure your jewelry is completely dry before you put it away!