Before wearing, wipe the sterling and gold setting with the enclosed polishing cloth to brighten and shine. Wipe off the pearl strand regularly with a damp cloth to remove the salts and oils that are deposited onto it from your skin.
To deep clean, spray the metal with Windex, scrub with a soft toothbrush, and rinse well. The seashell can be cleaned with soap, water, and a soft toothbrush if it gets dirty.
If you prefer, you can use Goddard's Silver Polish Foam. It is easy to control the application, and will not harm the shells or stones in your jewelry. Purchasing info is provided in the link.