The right way is to use a piece of fuel line hose, cover the end with old cotton t-shirt cloth and put a small amount of Simi-chrome on the end. Cover RCA jack by pushing tube with cloth over the jack and rotate back and fourth. Wipe jack off to remove Simichrome residue.
If you have gold plated jacks skip the Simichrome as it may remove the thin plating. Just use de-oxit on the cotton cloth. The advantage of this is that you can totally clean very closely spaced jacks.
Thanks,
Ron-C