Be sure to Examine Holiday Lights Before Hanging Them, Buy High-Quality, Outdoor Lighting, Buy LED Lights, Not Incandescent Lights, Plug Outdoor Lights Into GFCI Outlets, and Keep the Cords and Outlets Dry. Meanwhile, avoid Using Nails, Tacks, or Staples to Secure Outdoor Lights, Using Outdoor Lights Indoors, Daisy-Chaining Your Christmas Lights, and Connecting LED and Incandescent Lights Together.