I clean my pipes after every smoke. I use multiple BJ Long tapered fuffies for the stem. Once I am done with those I double them over and wipe the inside of the bowl getting rid of any loose ash or tobacco. I then blow out through the bowl making sure nothing sticks to the inside. I then take a tapered bristled cleaner,double it over and slide it back and forth down the shank multiple times till cleaners come out clean. Once that is done i take a bristled cleaner and double it 4 times and jam it down the mortise to clean out that.
Maybe once every couple of years I will do a deep clean using shank brushes, ever clear and my senior reamer.
I forgot to mention on every pipe I clean I use Obidisian Stem Cleaner to keep my stems looking great. Nothing is better than lighting up a fresh pipe.