This achievement is missable. As far as I know, it only can be unlocked in a specific room during Chapter 6. That room is the one with a triple moving platform that you have to climb.
As for now, the exact requirements for the achievement seem unclear, but I can confirm that using the platform to launch yourself as shown in this video works.
If it doesn't unlock the first time, repeat the process several times, varying position a little, or pushing
during launch, and it will unlock eventually.
If my method doesn't work, try this alternative way, as suggested by Strud
in the comments:
When you are standing on the edge of the platform about to activate the button to launch yourself, look down at your feet. You need to position yourself so that you can fully see the animated yellow/black edge of the 2 buttons below closest to the wall (you should just see the edge of the blue pad you used to get up there). Look up and launch - you should fall off the edge of the platform at the peak of the flight and fall to the ground below, unlocking the achievement.