Where to get?Edit
To get glider you need to be in Chapter Four of story. After Missing Survivors one of NPC will give you this.
How to use?Edit
To use the glider, you press space while falling. It only opens after falling a second or so, making it necessary to jump off a tower or rock in order to use it. While flying, A and D steer, W points downward, and S points upward. When pointing downward, you gain speed, but lose altitude much more quickly, and vice versa. Pressing neither W nor A will keep your speed at an equilibrium.
Combo with JetpackEdit
The glider rapidly transports you long distances with the help of the jetpack. If you put both in your hotbar, you can quickly rocket off the ground with your jetpack, then switch to the glider to soar. This is the fastest way to travel without a vehicle.