Double Jump 5 times without touching ground
Ori and the Blind Forest AIRBORNE Achievement Guide
A very easy spot to get this is near the top of the Ginso Tree. You can use the two teleporters that are on the top and bottom of the room to jump in an endless loop through the room. Simply jump to the right and fall into the teleporter and repeat.
The downside is that this spot is can’t be accessed after you completed the Ginso Tree.