The Huawei Mate 8 offers four different ways to take a screenshot.

Method #1

1. Hold down the Power and Volume Down buttons simultaneously

Method #2

1. Pull down the notification shade
2. Swipe over to Shortcuts (if not already there)
3. Tap the Screenshot button

Method #3

1. With one knuckle, double-tap the display

Method #4

1. With one knuckle, tap the display and hold down
2. Drag your knuckle around the section of screen you'd like to screenshot
3. Lift knuckle

Whichever method you use, all screenshots can be found in the Gallery app under Albums > Screenshots.