https://www.metv.com/stories/ken-curtis-stayed-just-as-dirty-as-his-character-on-gunsmoke

Ken Curtis didn't mind being dirty... it's just what the role called for.

Ken Curtis had this clever trick to keep Festus looking filthy on Gunsmoke (https://www.metv.com/stories/ken-curtis-had-this-clever-trick-to-keep-festus-looking-filthy-on-gunsmoke)

A little effort went a long way in building an authentic wardrobe for a well-worn character.