I think it depends on "what type of Judge", you are showing under. I remember years ago, competing in a Ladies Driving Class under a Judge who turned out to be a "Carriage Driving" man, and he lined us ladies all up and lectured us stating, "Ladies should look like Ladies", meaning hats and gloves.!! But for your Mini Horse Judge, depends on the type of show either local Fair, sanctioned, or Nationals. But should be neat, clean and tidy looking. I personally like long sleeves with gloves; hats are optional, some wear them and some don't.