macOS Catalina is a hugely exciting upgrade for the Mac. In some ways, it’s like having a completely new computer. You may have already taken the plunge and installed it, or maybe you’re waiting to see how it settles down before you install it. But whichever camp you’re in, it’s a good idea to create a bootable installer for macOS Catalina. That way, if anything goes badly wrong with your Mac, you’ll be able to boot from the installer and get going again quickly.
However, there are many ways to create a macOS USB flash drive installer like Disk Creator but the easiest way to create macOS Catalina bootable USB is using Terminal, which you don’t need to install and additional software. But before moving to our main topic, let’s have some piece of information about macOS Catalina, macOS Catalina. Make sure the USB drive is connected to the Mac. Next, click on the Apple logo from the top left and choose Restart. When you hear the startup sound or see the Apple logo, immediately press and hold the Option key. Select the bootable installer as the startup disk, and follow the instructions. To save you the trouble, here’s a list of macOS installers: macOS Catalina; macOS Mojave; macOS High Sierra; macOS Sierra; OS X El Capitan; Create bootable USB drive with Mac Disk Utility. Now that you have the installation files ready on your Mac, you can move them to your USB drive for future use. To install macOS on an external hard drive: 1. Download and create macOS Catalina USB bootable disk. Download the latest version of the app from dosdude’s portal and mount the dmg file on your Mac. Click continue until you see the window shown in the screenshot. Here you may select an existing copy or macOS Catalina or download one from the Internet.
There are a number of reasons for creating a bootable USB Mac installer.
You can use an external hard drive, an SSD or a USB stick. Anything that has at least 16 GB of free space. You’ll need to create a new partition (or container if it’s formatted as AFPS) for the installer so if you have data on it you need, you should copy it to another drive first.
Whoa! Not so fast. There’s one more thing you should do before you create the installer: clear out the junk on your Mac. Before you undertake any major task on your Mac, and especially before you install a new version of the operating system, you should clear out junk and old files you no longer need. I don’t normally recommend software tools, but in this case, the nest way to clear out the clutter is to use CleanMyMac X. It can scan your Mac at the press of a button, identify all the files you don’t need, and allow you to get rid of them with one more click. Here’s how to use it:
Once you’ve cleared out the clutter, you can go ahead and create your bootable installer. Here’s how:
The installer has now been saved in your Applications folder. You can go ahead and check, if you like. You now have two options for creating the installer. If you’re comfortable with using Terminal, you can go ahead and jump to the instructions for that, below. If you’d rather not use Terminal, there’s a neat utility called Diskmaker X that will do it for you. All you need to do is download and install it and then, when you run it, point it to the macOS Catalina installer you just downloaded. There are full instructions on the download page.
sudo /Applications/Install macOS Mojave.app/Contents/Resources/createinstallmedia —volume /Volumes/Untitled
where ‘Untitled’ is the name of your USB stick or external hard drive
You now have a macOS Catalina installer on an external disk or USB stick. Eject it, unplug it and keep it safe. You can use it to install Catalina on any Mac that supports it.
Once you’ve used tour new installer to install Catalina on a Mac, it’s a good idea to update all your applications so that that are Catalina compatible. You can do this manually, from the App Store and by launching non-App Store apps and choosing check for updates, but that’s a long and tedious process. It’s much quicker and easier to use the updates in CleanMyMac X. Here’s how you do it.
And that’s it. You’re done. CleanMyMac X checks all your installed apps for updates and then updates them all.
Creating a bootable installer for macOS Catalina isn’t difficult. If you have a spare disk or USB stick and are comfortable using Terminal, you can do it right away. If you’d rather not use Terminal, use the Diskmaker X tool described above. Whichever method you use, make sure you use CleanMyMac X to clear out the junk on your Mac before you start, and use it again to update your applications when you’ve finished.