How do you turn the I watch off?

Hi

To turn off your Apple Watch: press and hold the side button (the lower of the two buttons) until the power off slider is shown, then slide the Power Off slider to the right:

• Turn on, wake, and unlock
• How to restart your Apple Watch - Apple Support

Note that it is not possible to turn Apple Watch off whilst it is on the charger and connected to power - this is normal.

Keep in mind that, during general daily use, it should not typically be necessary to turn your Apple Watch off and on again.

Rather than doing so regularly, you may find it more convenient to place your Apple Watch on the charger whenever you are not wearing it, including nightly, overnight.

Apple advises that you can charge Apple Watch whenever you want. There is no need to let the battery discharge to any particular level first, nor any benefit to be gained from doing so:

Batteries - Why Lithium-ion? - Apple

The watch cannot be overcharged and the battery will not suffer any harm from regular charging. Charging will stop automatically when the battery is fully charged and start again if and when required due to ongoing battery usage.

Be sure to follow Apple's safety and handling instructions and also note that it is normal for your Apple Watch, power adapter and charging cable to become warm when connected to power.

More information:

Check your battery and charge your Apple Watch - Apple Support

Keep Apple Watch within acceptable operating temperatures - Apple Support

Important safety information

Hello,

Turn off Apple Watch. Normally, you’ll leave Apple Watch on all of the time, but if you need to turn it off, press and hold the side button until the sliders appear, then drag the Power Off slider to the right.

Turn on Apple Watch. If Apple Watch is off, press and hold the side button until the Apple logo appears (you might see a black screen for a short time first). The watch face appears when Apple Watch is on.

From:

Turn on, wake, and unlock - Apple Watch User Guide