Cleaning up/polishing up a nickel silver Shaw high C whistle

Hi there, Just recently I purchased a Shaw high whistle. It’s made of nickel silver. It is getting tarnished (brownish in color) already. Is there a gentle safe way to polish it without harming it yet giving that clean youthful shine that it had when I took delivery of it?

Tin
(No relation to Rin-Tin-Tin) :smiley:

See this post: https://forums.chiffandfipple.com/t/need-help-recommend-a-polishing-cloth-for-brass-whistles/64441/1