Just water and scrap paper. I don't like using cleaners - I've had bad experiences where they eventually made my clear stamps so they wouldn't stick to blocks. If there is ink in the crevices, I'll use running water right after I use the stamp. Most of the time, I just stamp off the excess ink onto textured scrap paper.
After a while, most stamps don't come completely clean. It doesn't make a difference in how they work though; they are just loved
I've used the technique Tuesday stamp cleaner sold in the store. You can do a search at the top for it (I would add a link but I'm on my phone and it's almost impossible for me to do). I agree that most clear stamps won't come completely clean, especially if you use chalk inks. Makes them all the more loved, in my opinion.
I use a Close To My Heart stamp scrubber. I usually just use water in a mister bottle to wet it but sometimes for the more stubborn inks I use stamp cleaner..I think the one I am using now is made by inkadinkadoo.
I used to be so fussy about cleaning my stamps. I'd use a scrubber and a stamp cleaner. Then I discovered that some of the scrappers that I most highly admire on this site simply blot their stamps onto paper until there isn't any more ink coming off. I felt free!
I bought one of those fuzzy cleaner pad things that opens like an ink pad used at a garage sale and have never used it cause I thought I needed some sort of cleanser stuff for it. lol But I think i'll just try spraying water on them and rubbing them on the fuzzy part of the pad. but usually i'd take them into the kitchen and wash them off and take a paper towll to them to dry them. But on occasion i'd just blot them on a scrap of paper. lol
Glad to know that if there's a bit of remaining ink on them it doesn't hurt them.