Next, you’ll need about 5 GB of free space in storage for the upgrade. There are three ways to create a backup for your Apple computer: You can back your files up to another storage device (i.e., an external drive), upload your stuff to iCloud, or use Apple’s Time Machine app to create a disk image. This isn’t strictly necessary to have the upgrade work, but it’s great insurance against mishaps. First, any time you upgrade to a new operating system, it’s smart to first create a backup of your files. If you’re about to upgrade to macOS High Sierra, here’s some basic advice.
