With proper care, your jewelry can last for a long time
Clean your jewelry on a regular basis to remove substances that could discolor it.
Keep it dry! Removing your jewelry before showering or bathing is an excellent habit to establish
Apply makeup, hairspray or any type of lotion before putting on your jewelry, they may contain harsh chemicals that may damage your jewelry overtime.
Store jewelry separately so it doesn't scratch other jewelry... the best way is to seal and store in an air-tight plastic baggie to prevent tarnishing.
A polishing cloth is great way to clean and bring out the luster in your jewelry.
And lastly, always practice last on, first off.