It’s been a week since Halloween, so I sadly dragged all my tombstones and giant spiders inside. Christmas is coming, and that means it’s time to get festive with the lights. However, since we only put up Christmas lights once a year, it’s possible to make mistakes. Here’s the most important one to avoid.

Do not put your Christmas lights up backwards.

Make sure that the part of the string of lights that you want to plug into your outlet or extension cord is the male end. That’s the one with two prongs. I know, you’ve seen males naked, and they only have a single prong. One, I’m glad you’ve been dating again and two, if you prefer you can be like my dad and call it the goes-into.

You have to do this right because if you don’t, you’re going to be forced to take all the lights down and put them back up in the opposite order. That’s no big deal for me since I just lazily drape ugly glass bulbs over the garage door to appease my 1970s-obsessed wife, but you may be doing something far more elaborate that involves ladders and homeownership. Switching that around would take all day.

“Nonsense,” you say. “I will simply go to the hardware store and buy an adapter!”

A male-to-male adapter does not exist. In general, they’re illegal to sell. Sometimes people make their own because it is amazing the lengths people will go to in order to avoid admitting they made a simple mistake. The results of these horrific abortions of electrical engineering are called suicide cords, or sometimes suicide cables.

Basically, once you plug one end into the electricity, it is now grounded and flowing through the other end. That includes the exposed metal prongs. An extremely careful person could possibly insert that end into the mishung lights without incident.

You are not an extremely careful person because you put your damn lights up backwards. In reality, you are probably going to end up touching the exposed prongs and sending a house current through your highly conductive and very stupid self.

Will that kill you? Maybe. About 5,500 people go to the emergency room each year from accidents that involve electrical outlets. Some of them die, particularly if they are older, have underlying health conditions, or failed to secure protection from lightning.

So, be smart. Write “do not hang backwards” on the box of holiday decorations. Check all your lights before they go up to make sure there are not shorts or dead spots. During each step of the process, mentally extrapolate the remaining steps to make sure the end result is what you want. Plan ahead.

If not, you’re going to find yourself screaming at some poor hardware store clerk for an adapter that doesn’t exist and which you would be too bloody irresponsible to use even if it did. Learn to live with your mistakes. Do not try and cheat your way around them unless you want the Christmas spirit to enter you 120 volts at a time.