I assume you mean a Arkansas oil stone. The best think to do is keep it clean use plenty of oil norton brand from the home depot works well. I have uses instrument oil but is harder to come by and more expensive. Wipe off the dirty oil after each use.
smiths recommends cleaning with soap and water after each use. scrub with a nylon brush.
and yes occasional lapping if needed to true them.
I have a couple stones that I have had for years I just use plenty of oil cant say I have ever used soap and water on them.
I came across this document a little OT but a classic worth a read
Norton Sharpening guide