# Grabbing the macOS installer

Grabbing macOS is actually quite simple, however Apple restricts access to newer installers on older Macs. To resolve this, we'll actually use gibMacOS to grab the OSes straight from Apple's servers.

# Downloading macOS

The process is simple:

Download gibMacOS then run the gibMacOS.command file

Change software Catalogue(Optional, only for betas)

  • Big Sur: Press M to change the Max OS, then enter 10.16 to switch the (update) catalog to the Big Sur one.

Press C to change the catalog, then select the number for the developer (for developer beta) or catalog.

Select the number for the Big Sur beta to start downloading it.

Once finished, open the InstallAssistant.pkg that was downloaded - it will be located in the gibMacOS/macOS Downloads/developer/XXX-XXXXX - Install macOS Beta folder. This package from Apple will create Install macOS Big Sur Beta.app in your /Applications folder.

Run the InstallAssistant.pkg and point this to whichever drive you're booting off of, this is where the Install.app will be dropped:

Once done, you should find it located in your Applications folder:

# Creating the installer

To create the USB is quite simple, grab your USB drive and open Disk Utility in macOS. Next format as follows:

  • Name: MyVolume
  • Format: macOS Journaled
  • Scheme: GUID Partition Map

Once this is done, run one of the following commands:

# Mojave
sudo /Applications/Install\ macOS\ Mojave.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume

# Catalina
sudo /Applications/Install\ macOS\ Catalina.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume

# Big Sur - beta
sudo /Applications/Install\ macOS\ Big\ Sur.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume

This will take some time so you may want to grab a coffee, once done you can head to the next page.

Last Updated: 11/10/2020, 9:12:28 PM