Installing macOS High Sierra is as simple as opening up Mac App Store and downloading it. However, there are instances where you might need to create a bootable USB flash drive for macOS High Sierra for a clean installation or to install on other Macs which might not have a fast Internet connection. Normally, a bootable drive is created using the Terminal in macOS. Luckily, there are a few free apps that make it easy to burn macOS to a usb drive with just a few clicks and without any command line.
A macOS bootable USB installer is helpful in scenarios where a you might want to perform a clean install on your Mac by formatting existing data. Even though macOS is available in the Mac App Store, which makes the update process easy, starting from scratch helps minimize any sorts of issues with app compatibility, data or system caches. A macOS bootable USB can also come in handy in case you want to install it on another partition or on another Mac. Through it can be used for recovery purposes too, it is rarely needed as all Macs feature Internet Recovery.
Before you use the following apps, ensure that you have downloaded macOS High Sierra from Mac App Store. To verify that the installer is in your system, you can open Launchpad to see the macOS installer icon. The installer file is required by these apps to create the bootable drive.
Create bootable macOS High Sierra USB drive
One of the best apps is DiskMaker X. DiskMaker X has been active since OS X Lion was released. The developer behind the app always keeps it updated whenever a new macOS version is released.
Once you download and launch DiskMaker X, simply click on macOS button and it will find your downloaded copy. Use a USB drive with minimum storage capacity of 8GB and it will begin the process. The USB drive will be formatted during this process so make sure that you do not have any important data on it.
The app might ask for administrator access to your Mac which you can safely provide by entering your account’s username and password.
Another great little utility is Disk Creator. It is a bit more user-friendly when compared to DiskMaker X because everything is done from a single screen interface.
Restart Mac using bootable USB
Once you have create a USB installer by using any of these apps, restart your Mac and hold down the Option key when the screen turns on. You will see the Startup Manager which will show your bootable drive as an option to boot from. Select your drive and hit return to boot from it and start the installation process.
Download DiskMaker X
Download Disk Creator