And I download the latest copy of the DiskMakerX 10.12 utility.While doing all of the above I download the macOS 10.12 installer.I set the first partition as 12GB for the installer (more than is needed), and then the rest for the Utility partition. Then reformat the drive as “Mac OS X Extended (Journaled)” and with a “GUID Partition Table”. Using Disk Utility, format the drive as ExFat. Setting up the USB drive takes a bit more effort under MacOSX 10.11.

I now use a SanDisk Extreme CZ80 64GB USB 3.0 Flash Drive.

Ars Technica has an updated set of instructions for macOS 10.12, but I stick with the old approach using the updated version of the DiskMakerX utility for macOS 10.12. [ Update: I used the Ars Technica: How to make your own bootable OS X 10.11 El Capitan USB install drive instructions to create a macOS 10.12 install USB drive.

Paste the appropriate createinstallmedia command from Apple’s CreateInstallMedia support page in Terminal to create the bootable installer.

Open the Terminal app, which is in the Utilities folder of your Applications folder.

and an 8 GB extra partition (in case I need to make it ExFat or FAT for file transfers.) (I use 12 GB for the installer, 42.1 GB for a “Rescue Drive” with a fully bootable OS, installer, Drive Genius, etc. You could also use a secondary internal partition that has at least 12GB of available disk space for the installation files.

Mount your USB flash drive or other volume.

The installer will be in your Applications folder. Quit the installer if it opens automatically after downloading.

Download the macOS installer from the Mac App Store.

Go to Apple’s CreateInstallMedia support page for up to date instructions.

Use the ‘createinstallmedia’ command in Terminal I tried using Apple’s CreateInstallMedia instructions, and finally was able to create a working Install device and Utility drive per my additional instructions below. After letting Diskmaker X do it’s thing, the drives (when I try using the whole drive as the installer) and partitions (how I normally do it) are not seen by Mac OS as bootable in the “Startup Disk” System Preference or when holding down the Option key on boot/restart.

Or if you want extreme speeds go for SanDisk SDCZ880-128G-G46 Extreme PRO 128GB USB 3.1 Solid State Flash Drive (This drive has a 380 MBps write and 420 MBbps read speeds for super fast installs)ĭiskmaker X has been problematic for me of late, I cannot seem to create a “bootable” USB drive from any of my Samsung USB drives.

Try using a Sandisk Extreme Go 64GB USB 3.0 (3.1 Gen 1) Type-A USB Flash Drive – SDCZ800-064G-G46 (This drive has a 150 MBps write and 200 MBbps read speeds for faster installs).

Creating an os x boot disk