How to Turn Off Apple Watch (And Force Restart It)
Hold the side button, tap the small power icon in the corner, then drag the Power Off slider. Here is the full sequence, screen by screen, plus what to do when the watch is frozen.

Hold the side button, tap the small power icon in the corner, then drag the Power Off slider. Here is the full sequence, screen by screen, plus what to do when the watch is frozen.

Menus move, settings get renamed and features quietly disappear. So each guide is written against the vendor's current documentation rather than from memory, and says plainly when a fix depends on your version.
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