It’s actually pretty easy. This YouTube video goes over the details, but basically:

Make sure the light show is on attached storage (given how light shows change, it’s a good idea to just keep all light shows up a USB drive; some people have a USB hub plugged in to the USB port in their vehicles to make it easier to access a USB port). If you only have one USB port and it’s got something in it (for, say, Sentry), gracefully remove it by stopping DashCam recording first (on settings screen, press and hold the DashCam video until it beeps and indicates recording stopped).

You can in fact have Sentry running during a light show.

• In the car, go to Toybox, Light Shows, select the show and options, and schedule it
• Or from the app (as long as you’re running the latest / recent version), go to Schedule, Light Show), select the options, and schedule it. Note that with the app, Sentry mode cannot be on and if you do dance moves, the car must be unlocked.

Some things to note:

• When you schedule a show for a later time, you have to then select whether you want dance moves (opening and closing trunk/frunk, moving mirrors). Selecting dance moves and then scheduling will reset dance moves, because that is something they want to be sure you are sure to select if you won’t be right there.
• If you’re doing this in a group, someone will let you know what time, what volume, whether or not you should select dance moves, and for vehicles equipped with air suspensions, what height to set.
• Please be sure to select the correct light show and time. It only takes one vehicle playing the wrong one to ruin the show for everyone. It’s easy to do, so double-check what you choose please.
• Software versions prior to the 2024 Holiday Update had an annoying bug that prevented USB drives with light shows from being seen by the vehicle. There were workarounds, but everyone’s running the latest Tesla firmware, right?
• Once you schedule the light show, exit the vehicle. It will not play if someone is in there.
• Because of that last point, do NOT go back to your vehicle until after the show is over. No opening doors, trunks, or frunks, as that will cancel the countdown. Take anything you need (jacket, water bottle, chair, whatever) with you.

Tesla Light Shows are a fun feature that Tesla introduced in the Holiday Update for 2021, software version 11. Before, the Model X could do its dance but this update allowed Model 3, Y, and S to join the fun.

The 2024 Holiday Update allowed for multi-vehicle synchronized light shows (which is really a better way to edit light shows that still have to be unique to each vehicle by coordinating which ones get which USB drives).

If you have a Model S that’s 2021 or newer, a Model X that’s 2021 or newer, any Model 3, any Model Y, or any CyberTruck, you can do custom light shows.

Perhaps the best reference for more information is Simon Pollock’s xlightshows.io website. But you can Google ‘Tesla light show’ and get a few billion suggestions (slight exaggeration).