Since our products are all made with Sterling Silver the best way to keep them looking polished is to wear them!
If the jewelry is to be stored for any length of time just keep them in an airtight ziploc bag as it is the air that tarnishes and oxidises the silver.
I recommend Wrights Silver Cream to wash and polish your jewelry, it's gentle and will not harm the gemstones.
Another effective method is to place your Sterling jewelry in an aluminum foil dish, sprinkle with baking soda and pour boiling water over them until just submerged. The tarnish magically disappears. You will probably need to repeat this process if the jewelry is heavily tarnished. Works on household silver too!