Some breeds of dogs -- such as the brachycephalic or flat-faced breeds like pugs -- should be walked on a harness and not a collar to prevent injury such as an eyeball popping out of the socket. Large, long-nosed dogs like Siberian huskies enjoy pulling a sled, wagon or bicycle using a harness, giving them an energy-burning workout. If your dog is chafing where his body contacts the harness, a little padding can remedy the situation.
While any soft fabric is suitable to pad your dog's harness, micro-fleece provides an ideal material. The tiny synthetic fibers resist tearing, don't readily absorb unpleasant smells or stains and won't create nearly as much friction as most natural fibers where they contact your dog. You can buy micro-fleece by the yard at any fabric store and cut strips to a desirable width. Wrap the strips around the harness several times until you achieve the desired thickness. Secure with a few stitches or fabric glue. Alternatively, sew several layers of fleece together and attach to the inside of your dog's harness with hook and loop fasteners such as Velcro to make removal for washing a cinch. Wash fleece in a machine or by hand for use time and again.