Mix a few drops of mild dish soap with warm water
Soak the silver necklace for a few minutes
Gently rub with a soft cloth or soft toothbrush
Rinse with clean water
Dry completely with a soft lint-free cloth
Use a silver polishing cloth to remove tarnish
Apply a small amount of silver polish if needed
Buff gently until shiny
Store the necklace in an anti-tarnish pouch or airtight bag
Keep it away from moisture, perfume, and lotions