As iOS 18.1 begins rolling out worldwide, it's essential to prepare your iPhone for a smooth upgrade experience. ZDNET recommends taking the following precautions: Ensure your phone can get the update by checking the A12 Bionic chip or later; Back up your data in case of issues; Update all apps manually instead of relying on automatic updates; Free up at least 1 GB of space to speed up the process; Disable Automatic Updates if you plan to delay the upgrade; and finally, use a fast and reliable internet connection for the update.

Source: https://www.zdnet.com/article/8-ways-i-prepped-my-iphone-for-ios-18-1-and-i-recommend-you-do-too/