Make sure to create a macOS Catalina USB installer before you update your MacBook and start exploring Catalina features. While you don’t need a bootable installer to install macOS Catalina, it’s a good option for people with a limited or sporadic internet connection, multiple Macs, or who want a backup installer for emergencies. Step 1: Download macOS Sierra from the Mac App Store. To create a USB installer for macOS Sierra, you first need to download the installation application from the Mac App Store. Using a compatible Mac, simply launch the App Store, find Sierra from the homepage sidebar, and download the installer. Once it has completed the download, the Sierra.
When you install a new major version of OS X, or after some time has passed, it is a good idea to do a clean install (that is, to erase the disk you are installing OS X onto as part of the installation process).
That will make your Mac run blazingly fast for a few months or more, and many people report that it fixes longstanding problems they’ve had too.
It used to be common practice to occasionally run a clean install, and then manually migrate all the files and settings over in order to get a completely fresh start. However, it has been shown in recent times that in the vast majority of cases if you simply run a clean install, then duplicate your old home folder to your new disk, you will get all of the same advantages as a clean install followed by manual migration, with a small fraction of the effort.
Here is the clean install procedure which can be performed at least every time a new version of macOS is released:
At this point, after a reboot and some minor adjustments (the Dock may not have your previous configuration for example, if you did this while logged into the same user account as you just updated), your new OS should be indistinguishable from your previous one, while being faster and smaller due to reduced clutter.
These advanced steps are primarily for system administrators and others who are familiar with the command line. You don't need a bootable installer to upgrade macOS or reinstall macOS, but it can be useful when you want to install on multiple computers without downloading the installer each time.
MyVolumein these commands with the name of your volume.
* If your Mac is using macOS Sierra or earlier, include the
--applicationpath argument and installer path, similar to the way this is done in the command for El Capitan.
After typing the command:
Yto confirm that you want to erase the volume, then press Return. Terminal shows the progress as the volume is erased.
Determine whether you're using a Mac with Apple silicon, then follow the appropriate steps:
A bootable installer doesn't download macOS from the internet, but it does require an internet connection to get firmware and other information specific to the Mac model.
For information about the
createinstallmedia command and the arguments you can use with it, make sure that the macOS installer is in your Applications folder, then enter the appropriate path in Terminal: