Realistic setups for tired parents, sorted by how much effort they actually take at eleven at night.

I plan routes for a living, which means I spend my whole year working out how to do the most with the least time. So I have strong opinions about Elf on the Shelf ideas that require a craft shop trip.
Every idea below uses things already in your house and takes five minutes or less. Some take thirty seconds. I have sorted them honestly.
For the nights you remember as you are turning off the light.
Slightly more staging, still no supplies.
For weekends, or when you have energy.
It happens to everyone, and there is a fix that works better than panicking at six in the morning.
Leave the elf exactly where they were and have them apologise. A tiny note saying the elf was too tired to fly last night, or got stuck reading, turns a mistake into character. Children accept a sleepy elf far more easily than parents expect.
The families who struggle are the ones who set an impossible standard in week one. Forty different setups is not the goal. A child who looks forward to the morning is the goal.
Do not make the mischief messier than you are willing to clean up. Flour on a dark bench looks wonderful in a photograph and takes twenty minutes to remove at half past six on a school morning.
Every idea above is designed to be tidied in under a minute, which is why I use them.
The elf works because it is the same small surprise every day, not because any individual setup is brilliant. Consistency beats creativity here, and consistency is much easier when the bar is a mug and a shoelace.
Pick ten from the first tier, keep them for the hard weeks, and you will get through December without resenting a small plastic elf.
The elf works best when children understand who sent them. Families who have Santa mention the elf by name find the whole tradition holds together better, because the two halves of the story finally meet.
Have Santa introduce your elf in a personalised message.