Tips and Hacks for Bootable Installer Creation on Mac

Every Mac user can recollect a rainy day on which they failed to start their dedicated companion and storage of all vital programs and files. The computer may simply refuse to turn on in any way, forcing you to seek alternative ways for recovering it instead of a safe boot mode or other First Aid measures. If you’re unsure what a bootable installer is, here is a simple guide for newbies covering every step of its creation and use.

Why Do You Need a Bootable Installer? 

Months or years of problem-free use of your Mac can be over one day, with the device refusing to start. The problem can be caused by a realm of issues that might have been accumulating in the system for some time. So, whether it’s a corrupted or virus-infected file, a problematic system update full of bugs, or a serious software/hardware failure, you’ll surely need an external macOS bootable USB to make the device work again.

In a nutshell, thus installer represents an external source of vital reinstallation or upgrade files to help your Apple OS get back to normal. By plugging this device into your non-operating Mac, you can start the essential processes and repair the critical Mac files to turn it on. 

Other situations in which you might need a bootable installer include a rollback to an older macOS version or an effort to install the operating system on a separate partition of your hard drive. The approach suits all of these goals, and here is how you can implement it. 

How to Create One? 

Now that we’ve clarified the significance of having a bootable Mac installer for a potential emergency, let’s deal in more detail with creating one. Keep in mind that it shouldn’t necessarily be another Apple device (though it would be an ideal scenario). You can use another Macbook, an iMac, or a Windows PC device as a bootable installer with ease. 

Before creating the bootable installer, please double-check that you have all technical items for its setup. These include: 

1. A non-functional Mac with the macOS pre-installed on it 
2. A trial version of TransMac software (for non-iOS devices) 
3. A USB flash drive with enough memory space to host the needed files (it’s recommended to use a USB flash drive with a minimum of 16GB)
4. A DMG file containing the copy of a macOS you need to install on the corrupted device. 

Once you have all the installation files and a USB flash drive with enough space, it’s time to proceed to the creation process. 

1. Plug in the external drive. 
2. Launch the Disk Utility function. 
3. Choose “View” in the drop-down menu and pick “Show All Devices” there. 
4. Choose the root drive in the menu appearing on the sidebar. 
5. Now, click “Erase.” 
6. Choose “Mac OS Extended” when you’re offered to select the required format.
7. In the Scheme section, you need to choose “GUID Partition Map.”  
8. Title your USB drive accordingly and click “Erase.”
9. Give your disk utility some time to create the partition and set the USB drive in the system, clicking “Done” after the process is over. 

Now it’s time to open the Terminal and copy the text corresponding to the macOS version you want to install into it. Once the name is inserted, click ”Enter/Return” and type your user password. Keep in mind that the Terminal will erase the drive completely, so if you’re comfortable with it, press “Enter” and wait for the disk’s erasure. After the disk is cleared, the Terminal will copy the installer’s files and will initiate the installation process.