I do not clean the bowl with regularity. Just make sure it is completely empty after smoking and wipe off the outside if it gets dirty. I never, ever, wax or buff.
I clean my pipe after every smoke. If the smoke is wet or if there is a gurgle in the pipe then I run a cleaner through it during the smoke. Afterwards I run a cleaner through the stem/shank and then I take the cleaner and make a 'u' shape and stick the cleaner in the bowl and clean the bowl out. If necessary I will use more than one cleaner and then when I'm done I blow down the stem to push any tobacco bits that didn't come out with the cleaners. I only do a salt treatment about once a year and only for pipes that get a ghost.
I'm with cmdrmcbragg (second post) on this one. I bought a bag of pipe cleaners but they don't fit through the mouthpiece. So I would have to unscrew the stem after every smoke or so, which would ruin the pipe in a jiffy.