Sterling silver jewelry stays clean if you wear it every day, but keep perfume and hairspray away from it. For cleaning use a simple jewelry polishing cloth and store your piece in a plastic zip-lock bag perhaps even with an anti tarnish strip. If you still notice tarnishing, try putting your piece in a glass bowl lined with tin foil. Dust the piece with baking soda and pour hot water on top. Use a soft toothbrush to remove it from the water and your silver should be shiny. Rinse off any remaining residue. To restore the shine on gold plating very gently rub with a non-abrasive jewelry polishing cloth.
Gold and brass jewelry can be cleaned with a jewelry cloth or a gently jewelry cleaner. Keep it away from perfume and hairspray which will tarnish it.