I have put my Kahr in the dishwasher before, just to see how well it cleaned it after reading that some actually do this. The results weren't all that spectacular to be honest. Scrub it down really good in hot soapy water, as others have suggested. Have a good assortment of small and large plastic and brass bristled brushes handy to get in every little crevice. Take the gun apart as far as you can while cleaning it. Run a bore brush through it with it submerged in said soapy water to loosen out all of the junk.
I also add a teaspoon of baking soda to the mix to help neutralize any acids that remain in the solution.
I use a plastic 1 gallon bin I bought from the grocery store for $4.99 for this. After scrubbing is complete, take the parts out and dry them the best you can with some soft, clean rags and then hose them down with non-chlorinated brake cleaner. It only takes a few very quick blasts into any crevices you can't reach to get any remaining water out. I then hit the freshly cleaned and degreased part with compressed air to blow out anything that could possibly remain. Add a little gun oil, hit with compressed air again and the part is ready for assembly.
This process takes a lot of time, and from reading it you may think it is very expensive however I get about 10-15 deep cleans out of a single can of brake cleaner and compressed air. These cleanings are good for long term storage or for after a few times at the range when you've had 500+ rounds through the gun. I have maybe $15.00 invested into my entire cleaning kit, plus chemicals, maybe another $12.00.
YMMV,
Ryan