System Preference > Software Update > Download macOS Big Sur. Note: If you have macOS Catalina, then follow the steps below to download Big Sur installer: The above procedure will download the installer file in your Applications folder as an app named Install macOS Big Sur/ Catalina/ Mojave/ High Sierra. If the installer opens after download, close the prompt without continuing the installation.

The installer file will start to download.In the App Store, you will find the macOS Installer, click on Get button on the top right corner.You can use the App Store to download the installer file. A prompt appears asking you to use the App Store instead of the website. It will redirect you to the Apple website.Click on the macOS for which you want to download the installer file.Follow the below steps to get the macOS installer file of Big Sur, Catalina, Mojave, and High Sierra: To create bootable USB for Mac, you need to first download the macOS installer file.

A downloaded installer file of the macOS version, for which you have to create the bootable USB installer for Mac.

A USB thumb drive or any other external drive formatted as macOS Extended, with storage capacity of at least 14 GB.

What’s Needed to Create Bootable USB for Mac?īefore you start, you need to keep the following things handy: If you want to know how to create a bootable USB to install macOS Big Sur, Catalina, Mojave, and High Sierra, then this post is for you. You can use this bootable USB macOS installer to perform a clean install of macOS, install macOS from USB on a separate volume of your Mac drive, or in case your Mac encounters OS issues. If you plan to install macOS on multiple Mac systems and don’t want to download the installer multiple times, then you can create a bootable installer.

Create bootable usb mac disk utility