1. **Open the Find My app**: Launch the "Find My" app on your iPhone. If you don't have it installed, you can download it from the App Store.
2. **Select your Apple Watch**: Tap on the "Devices" tab at the bottom of the screen to view a list of all your connected devices. Select your Apple Watch from the list.
3. **View Last Known Location**: If your Apple Watch's battery has died and it's not currently connected to your iPhone, you'll see its last known location on the map. This might not be accurate if the watch has moved since its battery died.
4. **Enable "Notify When Found"**: If you think your Apple Watch is nearby but can't find it, you can enable the "Notify When Found" feature. Tap on your Apple Watch in the Find My app, then toggle on "Notify When Found." Your iPhone will notify you when it detects your Apple Watch nearby.
5. **Use Sounds**: If your Apple Watch is within Bluetooth range (approximately 30-100 feet), you can use the "Play Sound" feature in the Find My app to make your Apple Watch play a sound, helping you locate it.
If your Apple Watch is dead and out of Bluetooth range, unfortunately, you won't be able to use the Find My app to locate it. In that case, you'll have to manually search for it in places where you typically keep or use your Apple Watch. It's a good idea to keep your Apple Watch charged regularly to avoid this situation.