*Note: this article is for the Oculus Rift S*
Firstly, make sure your Oculus Rift S headset is connected to your computer.
Open the Oculus application on your computer.
Find and select "Devices" on the left hand side menu.
Select the Rift S that you are using.
A side menu will appear to the right of your screen. Scroll down to and select "Guardian Setup".
You will be prompted to put on your headset.
Follow the Oculus instructions for setting up your guardian / play area to reset your height. Enjoy!