Soap, water, dry. Then I use a q-tip with 91% alcohol to clean 510, threads, contacts, etc. The I use a dab of NO-OX-ID (got a HUGE tube of this stuff I can pass to my great great grand-kids).
On atties with orings (or any orings) I use Bert's Bee Wax lip balm on a q-tip to make them smoove
Also, on my Provaris I use a white eraser to polish up the brass 510 - a trick pass down from the sages of the time and still works flawlessly.