Before you download watchOS 6, there are a few cleanup steps you should take to get ready for the big download.
If you’re worried about whether your Apple Watch can handle the watchOS 6 update, you can get prepared ahead of time by doing a little “fall cleaning” on your devices.
Hold off on backups; instead, clean up your iPhone and Apple Watch
You want your backups to be up-to-date when you make them, and that means doing them right before you update. Instead, take some prep time if you want it to do a bit of cleaning on your iPhone. Delete unwanted apps, get rid of offline music you no longer listen to, trim down any old Messages conversations you don’t care to keep. All of these will increase your backup size, and thus, the time it takes to upgrade. The same goes for your Apple Watch: Go into the Apple Watch app and remove any unwanted apps; and hey, maybe clean up your layout while you’re at it.
Make an encrypted backup via iTunes
Whether you’re doing a restore and install or just a straight update, we highly recommend making a backup beforehand in case anything crazy happens. Our current recommendation is an encrypted backup via iTunes — this lets you save your account passwords and Health data more quickly than doing so via iCloud. Your Apple Watch should make an automatic backup, but you can also manually back it up by unpairing and repairing your watch.
When updating, you’ll want to make sure you’re somewhere with a fast Wi-Fi connection — or, if you really want to super-power your download, get to a Mac with a fast Ethernet connection and connect your iPhone to that computer via USB cable, then update in iTunes. After updating to iOS 13, you’ll see the watchOS 6 update in the Apple Watch app.
If you have any questions or need any extra help, head on over to our discussion forums or leave a comment below!
Updated September 2019: Updated for iOS 13 and watchOS 6.
Source of the article – iMore