Connect a hard drive or USB drive to your computer. If the drive is larger than 1 GB, consider partitioning it to make a 1 GB partition for the recovery disk. (If you don’t create a partition, this process will use all of the available space on the drive, no matter how large it is.) Open the Recovery Disk Assistant application. This USB can be used to install a clean copy of Apple Mac OS X 10.15 Catalina or to update your existing system to 10.15 Catalina. Mac Mini:2012 onwards. Mac Pro:2012 onwards. Restart your mac. Insert the USB in your USB Slot. Here’s how you can create it. Make sure the USB drive is at least 8GB in size, and nothing else is stored on it. Download the macOS Catalina installation file using this link. Turn off the Mac and then insert the bootable USB drive. Now turn the Mac back on while holding the Option key. It will take you to the boot menu where you can select. Additionally, macOS Catalina drives the final nail in the coffin for 32-bit apps. They won’t run at all on Catalina. If you perform a clean install, you won’t have to worry about legacy software hanging around on your Mac.

After months of beta testing, Apple has rolled out macOS 10.15 Catalina to public users. You can download and install macOS Catalina if you have a compatible Mac. The macOS Catalina brings tons of new features such as the Apple Arcade, Screen Time, Voice Control, Sidecar, and Find My app. It has also replaced iTunes with three independent apps – Apple Music, Apple Podcasts, and Apple TV.

Is your Mac compatible with macOS Catalina?

Here’s the list of Mac devices compatible with the new software update:

• MacBook (Early 2015 or later)
• MacBook Air (Mid 2012 or later)
• MacBook Pro (Mid 2012 or later)
• Mac mini (Late 2012 or later)
• iMac (Late 2012 or later)
• iMac Pro (2017)
• Mac Pro (Late 2013 or later)

How to clean install the new software update

Upgrading to macOS 10.15 Catalina is pretty simple. Tap on the Apple icon in the top-left corner of the screen, then go to System Preferences > Software Update to download it. Alternatively, you can download it directly from the Mac App Store.

But sometimes upgrading macOS from the previous version to the latest one is not the best way. You might want to clean install macOS Catalina to give your Mac a fresh start without any issues from the previous installation. Here’s how to clean install macOS Catalina from USB drive:

Steps to install

• Take a full backup of all your important data. Save it to the cloud or an external drive
• You have to create a bootable USB drive. Here’s how you can create it. Make sure the USB drive is at least 8GB in size, and nothing else is stored on it
• Download the macOS Catalina installation file using this link
• Turn off the Mac and then insert the bootable USB drive
• Now turn the Mac back on while holding the Option key
• It will take you to the boot menu where you can select the USB drive. If your Mac has the T2 security chip, you have to first enable booting via external drives from macOS Recovery
• After a while, you’ll see the macOS Utilities menu on the screen. Select Disk Utility and then Continue
• Check to make sure you’ve selected the main drive of your Mac. Also ensure that the format is set as APFS or Mac OS Extended
• Now click Erase to wipe out the drive
• Once the drive has been erased, select Install macOS and then Continue. Just follow the on-screen prompts to clean install macOS Catalina

Once you’ve successfully installed the new software, you can transfer all your data back from the cloud or external storage drive to the Mac. Also, head over to the Mac App Store and re-install all the apps you want.

Apple hasn’t shipped operating systems on physical media in a full decade, but there are still good reasons to want a reliable old USB stick for macOS Catalina. Luckily, it's not hard to make one—either with a handy graphical user interface or some light Terminal use. Here's what you need to get started:

• A Mac that you have administrator access to. We've created a USB stick from both Mojave and Catalina, but your experience with other versions may vary.
• A 16GB or larger USB flash drive or a 16GB or larger partition on some other kind of external drive. A USB 3.0 drive will make things significantly faster, but an older USB 2.0 drive will work in a pinch; 8GB drives worked for Mojave and older versions of macOS, but the Catalina installer is just a little too large to fit.
• The macOS 10.15 Catalina installer from the Mac App Store (in High Sierra or older macOS versions) or the Software Update preference pane in Mojave. The installer will delete itself when you install the operating system, but it can be re-downloaded if necessary.
• If you want a GUI, take a look at Ben Slaney's Install Disk Creator from MacDaddy. There are other apps out there that do this, but this one is quick and simple.

If you want to use this USB installer with newer Macs as they are released, you'll want to periodically re-download new Catalina installers and make new install drives. Apple rolls support for newer hardware into new macOS point releases as they come out, so this will help keep your install drive as universal and versatile as possible.

There's also one new consideration for newer Macs with Apple's T2 controller chip—as of this writing, that list includes the iMac Pro, the 2018 Mac Mini, the 2018 MacBook Air, and 2018 and 2019 MacBook Pros, though Apple keeps an updated list here. Among this chip's many security features is one that disallows booting from external drives by default. To re-enable this feature, hold down Command-R while your Mac reboots to go into Recovery Mode and use the Startup Security Utility to 'allow booting from external media.' If you're trying to install an older version of macOS, you may also need to go from Full Security to Medium Security to enable booting, but if you're just trying to install the current version of macOS, the Full Security option should be just fine. And if you're just doing an upgrade install rather than a clean install, you can run the Catalina installer from the USB drive from within your current installation of macOS, no advanced tweaking required.

The easy way

Once you've obtained all of the necessary materials, connect the USB drive to your Mac and launch the Install Disk Creator. This app is basically just a GUI wrapper for the terminal command, so it should be possible to make install disks for versions of macOS going all the way back to Lion. In any case, it will work just fine for our purposes.

Install Disk Creator will automatically detect macOS installers on your drive and suggest one for you, displaying its icon along with its path. You can navigate to a different installer if you want, and you can also pick from all the storage devices and volumes currently connected to your Mac through the drop-down menu at the top of the window. Once you're ready to go, click 'Create Installer' and wait. A progress bar across the bottom of the app will tell you how far you have to go, and a pop-up notification will let you know when the process is done. This should only take a few minutes on a USB 3.0 flash drive in a modern Mac, though using USB 2.0 will slow things down.

The only slightly less-easy way

The Install Disk Creator is just a wrapper for the terminal command to create macOS install disks, so if you’re comfortable formatting your USB drive yourself and opening a Terminal window, it’s almost as easy to do it this way. Assuming that you have the macOS Catalina installer in your Applications folder and you have a Mac OS Extended (Journaled)-formatted USB drive (which is to say, HFS+ and notAPFS) named 'Untitled' mounted on the system, you can create a Catalina install drive using the following command.

sudo /Applications/Install macOS Catalina.app/Contents/Resources/createinstallmedia --volume /Volumes/Untitled

The command will erase the disk and copy the install files over. Give it some time, and your volume will soon be loaded up with not just the macOS installer but also an external recovery partition that may come in handy if your hard drive dies and you're away from an Internet connection. If you would like to create an install drive for a macOS version other than Catalina, just tweak the paths above to refer to Mojave or High Sierra instead.

Catalina Recovery Usb Windows 10

Whichever method you use, you should be able to boot from your new USB drive either by changing the default Startup Disk in System Preferences or by holding down the Option key at boot and selecting the drive. Once booted, you'll be able to install or upgrade Catalina as you normally would. You can also use Safari, Disk Utility, or Time Machine from the recovery partition to restore backups or troubleshoot.