SANTA CLARITA, Calif. (KABC) -- Clark Griswold's famous light installation in "National Lampoon's Christmas Vacation" is a reminder of what can go horribly wrong.
In the film, Chevy Chase takes a comedic tumble off the roof after trying to install a massive display.
In real life, Darell Lee has seen all kinds of disasters that are hardly funny.
"There's a broken bulb or an exposed wire," said Lee, a professional Christmas light installer. "They'll get a shock from that. People have gotten cut on the broken bulbs. I do know people who've used staple guns who hit themselves with the staple."
For homeowners who don't use a pro to install their lights, Lee offers a few tips.
For starters, don't install lights when it's windy or rainy. That increases the risk of a fall. Try not to run too many strands together, which can lead to a blown fuse. And be careful not to staple right through the wire.
Also, lay all the lights out on the ground ahead of time and make sure they work before climbing up the ladder.
Some homeowners know better than to risk it. Brian Blades of Santa Clarita has been using Lee's services for four years.
"There's no way I'm getting on the roof," he said.
Tips for safe holiday light installation