Since we're talking about #TTRPG prep, here is an old favorite.

One note: This is very much so a "Man Behind The Curtain" thingy, so if that sounds off putting to you, please avoid.

My secret technique is called "Lie to your players"

"You're in a room with two hallways leading out, which do you choose?"

Answer: They both go to the same place, but the players don't need to know that.

"We take the hallway to the right!"

Cool, here is a neat encounter with goblins and giant mollusks.

"We take the hallway to the left!"

Cool, here is a neat encounter with giant mollusks and goblins.

Players are convinced there was realistic depth, and you saved tons of time.

And if they choose to double back?

Maybe there is a week between sessions and you can prep further.

Or, if they go RIGHT THEN, just swap out Room 2 with Room 3.

The players don't know the layout of the adventure. Move it as you need.

"We double back and check out the hallway on the right"

Ah yes, and it looks like....*description of Room #3 prepped for later on in the dungeon, and have now taken out of time and space and plopped here*

As a DM, nothing is set in stone until you say it.

The world doesn't actually exist.

It's sense of realism and disbelief is only as deep as the players choose to go.

And here I am as a DM, pulling back the final curtain to reveal the most reviled truth in TTRPGs:

The illusion of choice is JUST AS IMPORTANT as actual choice.

Convince players they got a unique experience by choosing Hallway A.

It doesn't matter that it's not true.