Connect your iPhone to your PC with a USB cable
Unlock your iPhone and tap Trust This Computer if prompted
Open iTunes on your PC, or open the Apple Devices app on Windows if installed
Select your iPhone when it appears
Go to the Summary or General section
Choose Back Up Now
Select This Computer if asked where to store the backup
Wait for the backup to finish
Check the latest backup date and time to confirm it completed
To include passwords and health data, enable Encrypt local backup before backing up
To back up again later, repeat the same steps