If you’re hesitant to update your Mac to the latest version of macOS or want to test the beta before installing it on your system, you can install it on an external drive instead. This way, you can try it out without risking any data loss or software incompatibility. Plus, if you don’t like the new macOS, you can always go back to your old system.
This tutorial on how to install macOS Big Sur on external drive will help you make a bootable macOS Big Sur USB drive so that you can install the latest version of macOS on your Mac. From formatting your USB flash drive to permitting Mac to use the external drive as the startup disk, this guide will help you with everything.
What you Need to Create a Bootable Installer
To create a bootable installer for macOS, you need the following:
- USB flash drive that’s at least 14 GB in size.
- Copy of the Installer for OS X El Capitan or later.
A Step-by-Step Guide on How to Install macOS Big Sur on External Drive
Here’s how to install macOS Big Sur on external drive to try out macOS Big Sur’s features.
Back Up your Mac
First, you’ll need to back up your Mac using Time Machine. This is important because you will be reformatting your drive and erasing all of its contents.
To do this, open up Time Machine from the Applications folder and follow the prompts to set it up.
Format your external drive: Next, you’ll need to format your external drive. This can be done by opening Disk Utility (located in the Utilities folder), selecting your drive, and clicking the “Erase” button.
Download macOS Big Sur Installer
Once your drive is formatted, you can download the macOS Big Sur installer from the App Store. To do this, open up the App Store and search for “macOS Big Sur.”. Once you find it, click on the “Get” button and follow the prompts to download it.
Format the USB
After the macOS Big Sur installer has finished downloading, you’ll need to format the USB flash drive you’ll be using to install it.
The following steps will show you how to do this:
- Open Disk Utility (located in the Utilities folder).
- Select your USB flash drive from the list of drives.
- Click on the “Erase” button.
- Choose the “MacOS Extended (Journaled)” format and click on the “Erase” button.
- Close Disk Utility.
Create a macOS Big Sur installer
With your USB flash drive formatted, you can now use it to create a bootable macOS Big Sur installer. To do this, you’ll need to use the Terminal application.
Follow the steps below to do this:
- Open Terminal (located in the Utilities folder).
- Type in this command and press Enter: sudo /Applications/Install\ macOS\ Big\ Sur.app/Contents/Resources/createinstallmedia –volume /Volumes/Untitled (make sure to replace “untitled” with the name of your USB drive).
- Click “Return” when prompted.
- Wait for the process to finish. This can take some time, so be patient.
- Once it’s finished, you can close Terminal.
Permit Mac to Use External Disk
The next thing you need to do is allow your Mac to use the external drive as a startup disk. To do this, you’ll need to open up System Preferences and click on the “Startup Disk” icon. Click on the “Lock” icon and enter your password when prompted. This will allow you to make changes to the startup disk preferences.
With the startup disk preferences unlocked, you can select your external drive as the startup disk. To do this, simply click on the external drive and then click on the “Restart” button. Your Mac will now boot from the external drive.
Install new macOS Big Sur on an External Drive
The following steps will show you how to install macOS Big Sur on external drive:
- Insert your USB drive into your computer.
- Restart your Mac and hold down the “Option” key. Hold the Touch ID/Power Button until you see the startup manager.
- Select your USB drive from the list of drives.
- Under the “MacOS utilities,” select “Disk Utility.”
- Select “Install macOS,” then click Continue on the Utility page.
- Click “Agree” to the terms and conditions. On the next page, select your external drive as the destination to install macOS Big Sur and click “Install.” Wait for the installation process to finish. Once it’s finished, you can restart your computer and boot from the external drive.
Installing macOS Big Sur on an external drive is a great way to try out the new operating system without affecting your internal drive. It’s also a good way to create a backup if something goes wrong with the installation. And if you decide that you don’t like macOS Big Sur, you can simply delete the external drive and return to your old operating system.
Follow the above-mentioned steps, and you should have no problem installing macOS Big Sur on an external drive.