How to create a bootable macOS Big Sur 11.x USB install drive

News from: 9T05Mac

Making a bootable macOS Big Sur USB drive is a quick and clean way to install a fresh copy of macOS on your Mac. This hands-on tutorial is valid for both the public versions of macOS Big Sur, and will also work with the final version of Big Sur upon its release later this year. Simply follow our step-by-step guide for the full details.

Make sure that there’s nothing important that you need on the drive, because the full contents will be deleted. I recommend checking the contents, and then formatting the drive as macOS Extended Journaled (HFS+) via Disk Utility. Keep in mind that APFS-formatted drives cannot be used to create the macOS Big Sur USB installer.

How to create a bootable macOS Big Sur USB install drive steps as below.

Step 1: Download macOS Big Sur 11.x. From the Mac App Store. 

Step 2: After downloading macOS Big Sur, the installer will automatically launch. Close the installer.

Step 3: Open Finder → Applications. Right-click on Install macOS Big Sur → Show Package Contents.

Step 4: Open Contents → Resources.

Step 5: Launch a new Terminal window by going to Applications → Utilities → Terminal.

Step 6: Type sudo followed by a space in the Terminal window.

Step 7: Drag createinstallmedia to the Terminal window from the Resources folder noted in Step 4.

Step 8: Type --volume followed by a space.

Step 9: Open Finder → Go → Go To Folder…

Step 10: In the ‘Go to the folder’ box type /Volumes and click the Go button.

Step 11: Connect a USB flash drive to your Mac; it should appear in the Finder window.

Step 12: Drag the USB flash drive volume into the Terminal window.

Step 13: Press the Return key on the keyboard to submit the full Terminal command and when prompted, enter your password.

Step 14: When prompted type a “y,” and press the Return key on the keyboard to submit. Terminal may ask for access to files on the removable volume.

Step 15: The install process will begin by purging the contents of the connected USB drive. Afterward, the installer files will be copied to the drive. Because this process takes a few minutes to complete, you’ll need to exercise patience throughout the install process.

Using the macOS Big Sur 11.x USB installer

Creating the USB installer drive is easy, but actually using it can be challenging for users running Macs with Apple T2 Security chips. The aforementioned steps walk you through the basic process of creating the installer, but the video walkthrough goes even more in depth.

Details on how to enable booting from external/removable media via Recovery Mode are explained, along with direction on secure boot settings that I found helpful. Be sure to watch the full video for step-by-step details on how to utilize the USB installer drive once you’ve created it using the steps outlined above.

Step 1: macOS Big Sur USB Installer – startup security utility

Step 2: macOS Big Sur USB Installer – startup security utility

Step 3: macOS Big Sur USB Installer – secure boot settings

Step 4: macOS Big Sur USB Installer – connect flash drive

Step 5: macOS Big Sur USB Installer – hold option key for startup selector

Step 6: macOS Big Sur USB Installer 

Step 7: macOS Big Sur USB Installer – installing macOS Big Sur on new volume

How to create a bootable macOS Big Sur USB install drive [Demo Video]

When installing macOS Big Sur 11.x, you’ll have several options at your disposal.

1. You can choose to upgrade your existing macOS installation, going from macOS Catalina or previous versions of macOS to Big Sur.
2. You can erase your existing installation and start from scratch.
3. You can create a separate APFS volume and install macOS Big Sur there if you’d like to keep macOS Catalina around. Read and watch our tutorial about creating separate APFS volumes for macOS Big Sur for more details.

How to install macOS Big Sur public beta on a second APFS volume

Step 1: Download the macOS Big Sur beta. This download can originate from Apple’s Developer Center, or via the forthcoming Big Sur public beta.

Step 2: Open Disk Utility, select your current APFS volume, and click the + sign to create a new volume.

Step 3: Give your volume a name. I like to use a name like “Beta” to make it clear what’s housed on the volume. Ensure that APFS is selected for the Format and click Add.

How to install macOS Big Sur beta on a separate APFS volume (Demo Video)