quick way is a soft rag and tooth paste.
The quickest way is Goddard's silver dip. Another option is Goddard's long term silver polish cloth which is supposed to make the shine last longer.
Line a glass dish with aluminum foil with the shiny side up. Put the jewelry on top. Pour boiling water over the jewelry until it is covered. Then add 2 tablespoons of baking soda and 2 tablespoons of salt. Stir it to dissolve the salt and baking soda. Let the jewelry sit in it about 5 minutes. Rinse with water and buff with a lint free cloth. I've been doing this for years and it works well.