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How would one screenshot on a X?

Screenshots: Volume up + side button

Bring up power off menu: Press and hold volume down and the side button

Soft Reset: Press Volume up, Press Volume down, and then hold Side Button until you see the Apple Logo.
 
Example:

142717-phones-news-how-to-take-a-screenshot-with-the-iphone-x-image2-vf0c5kpqre.png
 
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