1993 Mercury Villager Turn signal short circuit

The turn signal fuse burns out regularly. I thought it might be weather related or movement related but while sitting at an intersection, on a dry day, waiting to turn, the flashers were working normally, then suddenly stopped because the fuse blew. Over the years it has become more frequent. Can a bad flasher unit blow the fuse? If I have to try and track down a short, what is the easiest/best way to do it?