Step 1 :
Climb ontop of the door of the elevator
Step 2 :
Activate the elevator from ontop of the door
Step 3 :
Jump down the elevator shaft
Step 4 :
Press W until you hit a wall
Step 5 :
Continue holding W after you hit any wall (this will slow you down)
Then you will slide down the wall and take no fall damage. Then you can just complete the next puzzle with all the music playing in the background.

Congratulations!
You just skipped the elevator part!
and thats it