Inspect light strings. Discard any that are damaged. Frayed or cracked electrical cords or broken sockets are leading fire hazards. 

Follow the manufacturer’s instructions for connecting multiple strings. The general limit is three strings.  Light strings with stacked plugs can usually accommodate greater lengths than end-to-end connections.

Replace burned-out bulbs promptly. Empty sockets can cause the entire string to overheat. 

Make sure outdoor lighting is UL-rated for exterior use. Exterior lights, unlike those used inside the house, need to be weather-resistant. The same goes for any extension cords used outdoors.

Don’t use outdoor lights indoors. They’re too hot for interior use. For the coolest bulbs and greatest energy efficiency, try LED lights, which come in a wide range of styles and colors.

Don’t attach light strings with nails or staples. They can cut through the wire insulation and create a fire hazard. Only use UL-approved hangers.

Take exterior lights down within 90 days. The longer they stay up, the more likely they are to suffer damage from weather and critters chewing on them. 

Store lights safely. Tangled lights can lead to damaged cords and broken sockets. After the holidays, coil each string loosely around a stiff piece of cardboard, wrap it in paper or fabric to protect the bulbs, and store in a sturdy container until next year.