1. What’s needed for a clean install on a Mac A backup of the disk before it’s erased. Two options are to use Duplicate (a free utility which can copy and paste an entire bootable volume), or Mac Backup Guru (a paid, fully featured backup utility with unique incremental backups capability) for that. Here is a detailed guide for the process. A Mac operating system installer. MacOS Big Sur can.
2. Oct 16, 2014 If you don't want to use Diskmaker X, Apple has actually included a terminal command that can create an install disk for you. Assuming that you have the OS X Yosemite installer in your.

1. Install Disk Creator Yosemite Download
2. Install Disk Creator Yosemite Full
3. Install Disk Creator Yosemite Windows 10
4. Install Disk Creator For Mac
5. Install Yosemite From Usb

Create OS X Yosemite Bootable USB Drive Step 1. Insert the USB drive or Disc on youir MAC and run the Disk Utility app from the Applications Utilities folder.

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.

What you need to create a bootable installer

• A USB flash drive or other secondary volume formatted as Mac OS Extended, with at least 14 GB of available storage
• A downloaded installer for macOS Big Sur, Catalina, Mojave, High Sierra or El Capitan

Download macOS

• Download: macOS Big Sur, macOS Catalina, macOS Mojave or macOS High Sierra
  These will be downloaded to your Applications folder as an app named Install macOS [version name]. If the installer opens after downloading, quit it without continuing installation. To get the correct installer, download from a Mac that is using macOS Sierra 10.12.5 or later, or El Capitan 10.11.6. Enterprise administrators, please download from Apple, not a locally hosted software-update server.
• Download: OS X El Capitan
  This will be downloaded as a disk image named InstallMacOSX.dmg. On a Mac that is compatible with El Capitan, open the disk image and run the installer within, named InstallMacOSX.pkg. It will install an app named Install OS X El Capitan into your Applications folder. You will create the bootable installer from this app, not from the disk image or .pkg installer.

Use the 'createinstallmedia' command in Terminal

1. Connect the USB flash drive or other volume that you're using for the bootable installer.
2. Open Terminal, which is in the Utilities folder of your Applications folder.
3. Type or paste one of the following commands in Terminal. These assume that the installer is in your Applications folder and MyVolume is the name of the USB flash drive or other volume you're using. If it has a different name, replace MyVolume in these commands with the name of your volume.

Big Sur:*

Catalina:*

Mojave:*

High Sierra:*

El Capitan:

* 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:

1. Press Return to enter the command.
2. When prompted, type your administrator password and press Return again. Terminal doesn't show any characters as you type your password.
3. When prompted, type Y to confirm that you want to erase the volume, then press Return. Terminal shows the progress as the volume is erased.
4. After the volume has been erased, you may see an alert stating that Terminal would like to access files on a removable volume. Click OK to allow the copy to proceed.
5. When Terminal says that it's been completed, the volume will have the same name as the installer you downloaded, such as Install macOS Big Sur. You can now quit Terminal and eject the volume.
   

Use the bootable installer

Determine whether you're using a Mac with Apple silicon, then follow the appropriate steps:

Apple silicon

1. Plug the bootable installer into a Mac that is connected to the internet and compatible with the version of macOS you're installing.
2. Turn on your Mac and continue to hold the power button until you see the startup options window, which shows your bootable volumes.
3. Select the volume containing the bootable installer, then click Continue.
4. When the macOS installer opens, follow the onscreen instructions.

Intel processor

1. Plug the bootable installer into a Mac that is connected to the internet and compatible with the version of macOS you're installing.
2. Press and hold the Option (Alt) ⌥ key immediately after turning on or restarting your Mac.
3. Release the Option key when you see a dark screen showing your bootable volumes.
4. Select the volume containing the bootable installer. Then click the up arrow or press Return.
   If you can't start up from the bootable installer, make sure the External Boot setting in Startup Security Utility is set to allow booting from external media.
5. Choose your language, if prompted.
6. Select Install macOS (or Install OS X) from the Utilities window, then click Continue and follow the onscreen instructions.

Learn more

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 the macOS installer is in your Applications folder, then enter the appropriate path in Terminal:

It was 2009 when Apple last released a new operating system on physical media. Things have proceeded remarkably smoothly since version 10.7 switched to download-only installers, but there are still good reasons to want an old, reliable USB stick. For instance, if you find yourself doing multiple installs, a USB drive may be faster than multiple downloads (especially if you use a USB 3.0 drive). Or maybe you need a recovery disk for older Macs that don't support the Internet Recovery feature. Whatever the reason, you're in luck, because it's not hard to make one.

As with last year, there are two ways to get it done. There's the super easy way with the graphical user interface and the only slightly less easy way that requires some light Terminal use. Here's what you need to get started.

• A Mac, duh. We've created Yosemite USB from both Mavericks and Yosemite, but your experience with other versions may vary.
• An 8GB or larger USB flash drive or an 8GB or larger partition on some other kind of external drive. For newer Macs, use a USB 3.0 drive—it makes things significantly faster.
• The OS X 10.10 Yosemite installer from the Mac App Store in your Applications folder. The installer will delete itself when you install the operating system, but it can be re-downloaded if necessary.
• If you want a GUI, you need the latest version of Diskmaker X app—we wrote this article based on version 4 beta 2, but if a 'final' version is released alongside Yosemite we'll update the article. This app is free to download, but the creator accepts donations if you want to support his efforts.
• An administrator account on the Mac you're using to create the disk.

The easy way

Once you've obtained all of the necessary materials, connect the USB drive to your Mac and run the Diskmaker X app. The app will offer to make installers for OS X 10.8, 10.9, and 10.10, but we're only interested in Yosemite today.

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Diskmaker X has actually been around since the days of OS X 10.7 (it was previously known as Lion Diskmaker), but it's more important now because Apple has made alterations to the installer that prevent easy USB drive creation using the built-in Disk Utility app. It's still possible to create a disk manually using a Terminal command (which we'll go into momentarily), but Diskmaker X presents an easy GUI-based way to do it that is less intimidating to most people.

Select OS X 10.10 in Diskmaker X, and the app should automatically find the copy you've downloaded to your Applications folder. If it doesn't detect the installer (or if you click 'Use another copy'), you can navigate to the specific installer you want to use. It will then ask you where you want to copy the files—click 'An 8GB USB thumb drive' if you have a single drive to use or 'Another kind of disk' to use a partition on a larger drive or some other kind of external drive. Choose your disk (or partition) from the list that appears, verify that you'd like to have the disk (or partition) erased, and then wait for the files to copy over. The process is outlined in screenshots below.

Install Disk Creator Yosemite Download

The only-slightly-less-easy way

Install Disk Creator Yosemite Full

If you don't want to use Diskmaker X, Apple has actually included a terminal command that can create an install disk for you. Assuming that you have the OS X Yosemite installer in your Applications folder and you have a Mac OS X Extended (Journaled)-formatted USB drive named 'Untitled' mounted on the system, you can create a Yosemite install drive by typing the following command into the Terminal.

Install Disk Creator Yosemite Windows 10

sudo /Applications/Install OS X Yosemite.app/Contents/Resources/createinstallmedia --volume /Volumes/Untitled --applicationpath /Applications/Install OS X Yosemite.app --nointeraction

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 OS X 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.

Install Disk Creator For Mac

Install Yosemite From Usb

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 Yosemite as you normally would.