My Series 10 seems to last forever with the following changes I made (though I haven’t measured it):
Brightness: Lowest Setting
Wake on Raise: Off
Automatic App Install: Off
Auto-Launch (when submitted): off
Auto-Launch Lice Activities: off
Show live activities in wrist down: off
Reduce Motion: On
Tap to talk: off
Double Tap: off
Cover to Mute: off
siri (listen for): off
Raise to Speak: off
Crown Haptics: off
Time in Daylight: off
Environmental Sound Measurement: off
Music Detection: off
App Store automatic downloads: off
Heart Cardio Fitness Notifications: off
Show Notifications on wrist down: turned many off
WatchFace
Too many live complications on a watch face drain battery so I minimized complications on my main watch face to two(date and weather), use widgets and optimize arrangement of honeycomb app screen.
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