To prolong the life of your jewelry, I do not recommend wearing it in water. Remove your jewelry before exercising, swimming, showering, doing the dishes, putting on lotions, oils, or perfumes. (I personally wear my sterling silver rings all the time and just make sure to polish and clean them periodically like I do my wedding bands.)
Nugold, Copper, Sterling Silver-These are pure metals and will naturally tarnish with time, a small white polish pad (it's kind of like a mini magic eraser!) is included with your order to shine your piece back up. Jewelry tarnish is the result of a natural chemical reaction between the jewelry and the surrounding environment where the jewelry becomes darkened or discolored. Humidity and individual body chemistry can contribute to the speed and severity of tarnishing. You can store your jewelry in a sealed baggie to keep it from tarnishing as quickly.
Aluminum- This metal is eco-friendly and a great alternative to sterling silver! This cuff is made from food-grade aluminum and is lead and nickel-free & non-reactive (hypoallergenic). Aluminum will never rust or tarnish. Because this cuff is light-weight, it is great for layering and stacking with other bracelets. If it does become gunky from misuse then cleaning with mild soap and water and drying with a soft cloth should clean it right back up.
Pewter- Pewter will not tarnish but it does naturally oxidize (darken) over time giving it an organic patina look. If you want your piece to look polished you can clean with mild soap and water and dry with a soft cloth. Another trick is to brush over it with steel wool to get the oxidization off. When not wearing, place your necklace in a small baggie or jewelry box.