Go to the map Rupture, and find this tree (it is located at the top of the hill with the warehouse)

Approach the tree with the upmost caution as it is sacred and usually campers like to hide around, then proceed to look down at the ground and crouch.

NOTE: It is very important you approach the tree from the angle shown in the pictures or else it won't work

Once you are crouched and in position you need to wiggle your way into the tree so you are clipping into it. You can use a combination of diffrent types of crouching to get inside for example using space while crouched or shift. Once you feel like you have clipped inside the tree stand up and while moving forwards jump if you get it right you will achieve flight, this step may take a few trys to get right but it is more than possible.

Congratulations, you are now high enjoy your newly found super powers and jump your way into the sunset!