Back up your computer, create a bootable USB drive and install macOS Mojave starting today.

It’s that time of year where Apple is releasing its new mobile devices and operating systems. Last Monday, September 17, Apple released iOS 12 as well as watchOS 5, and tvOS 12. Then, on Friday, September 19, the iPhone and Apple Watch new models were launched. Today, Apple releases macOS Mojave (10.14), the fifteenth major release the Mac operating system. There are some great new features, performance updates, and even the inclusion of some iOS apps — like Apple News, Voice Memos, and Home — included in this final version of macOS to support 32-bit apps. If you have managed updating your own system updates in the past, then you know that there is a fair amount of work that needs to be done before you can actually perform the update. If you want the best possible experience, we would recommend performing a ‘clean installation’ of the software so that you don’t pull over any bugs or corruptions that may have been stored in your computer since the last update. With that in mind, we have compiled, along with the help of, a comprehensive list of directions that describe how you can create a bootable USB drive of the system software and prepare your system for a clean install.


  1. Make a full backup of your Mac. You can do this by using Time Machine, creating a clone of your hard drive, or manually copying files to an external hard drive. MacSources is not responsible for data loss.
  2. Create a Bootable USB Drive of macOS Mojave (see instructions below)
  3. Boot a compatible Mac from the USB drive. Turn off the Mac. Insert USB drive. Turn on the Mac while pressing the ALT/OPTION button.
  4. Choose “Install macOS Mojave USB” from boot menu. When USB drive is loaded, connect your Mac to a WiFi network by clicking on the WiFi symbol in the top right corner of your Mac’s screen.
  5. Select Disk Utility from menu.
  6. Select the disk of your Mac from left sidebar (the root not partition).
  7. Click on ERASE on the top menu.
  8. Set the name as “Macintosh HD”
  9. Set format as Mac OS Extended (Journaled)
  10. Click on ERASE and confirm. This will delete all data on HDD.
  11. Wait until the end of the operation. DO NOT turn off your computer or stop the operation once it starts.
  12. Once it’s finished, close Disk Utility and go back to macOS Mojave’s first screen.
  13. Choose “Install macOS Mojave” from the menu.
  14. Follow the wizard to complete a clean installation of Mojave.
  15. After restart, follow the first set up procedure.



NOTE: In order to complete this step, you need the following.

  • macOS Mojave setup file downloaded from Mac App Store. You can find it into Applications folder of Mac
  • USB Drive at least 16GB without data (it will be formatted during this procedure)
  • Terminal app natively included on macOS and Mac OS X
  • Fast internet connection


  1. Download macOS Mojave from Mac App Store for free using a compatible Mac
  2. Insert USB Drive into the Mac where macOS Mojave was downloaded
  3. Perform a backup of USB Drive if it is not new/blank
  4. Select Disk Utility from Applications.
  5. Select the USB Drive on the left sidebar (select the drive at root not partition)
  6. Click on ERASE
  7. Set the name exactly as Untitled
  8. Set format as Mac OS Extended (Journaled) – Map partition (GUID)
  9. Click on Erase and confirm
  10. Wait until the end of the operation. DO NOT turn off your computer or stop the operation once it starts. It can take 
15-20 minutes.
  11. At the end of this function, close Disk Utility.
  12. Open Terminal from Applications.
  13. Copy the following command and paste it into the Terminal window. Hit the ENTER button to execute the command. (ignore “WARNING: “–applicationpath” is now deprecated.“ if appears on the Terminal)sudo /Applications/Install\ macOS\ –volume / Volumes/Untitled –applicationpath /Applications/Install\ macOS\ –nointeraction 

  14. Put your Mac admin’s password and press Enter (write it also if asterisk will not appear on screen)
  15. Confirm erasing and command as required
  16. Wait until the end of the operation. DO NOT turn off your computer or stop the operation once it starts. It can take 30-40 minutes.
  17. When Terminal shows “Done!” you can remove the USB Drive.