Aos que como eu estava tendo problemas na criação do Pendrive bootavel (command not found), aí vai a solução.
Create a MacOS Sierra Bootable Installer Drive
For MacOS Sierra 10.12 Developer Preview Betasudo /Applications/Install\ 10.12\ Developer\ Preview.app/Contents/Resources/createinstallmedia --volume /Volumes/SierraInstaller --applicationpath /Applications/Install\ 10.12\ Developer\ Preview.app --nointeraction &&say Done
For MacOS Sierra 10.12 Public Betasudo /Applications/Install\ macOS\ Sierra\ Public\ Beta.app/Contents/Resources/createinstallmedia --volume /Volumes/SierraInstaller --applicationpath /Applications/Install\ macOS\ Sierra\ Public\ Beta.app --nointeraction &&say Done
“Erasing Disk: 0%… 10%… 20%… 30%…100%…
Copying installer files to disk…
Making disk bootable…
Copying boot files…
Connect the USB drive to the Mac, remember this USB flash drive is going to be erased and formatted, so be sure nothing important is on that disk
Rename the USB flash drive to “SierraInstaller” without spaces (you can pick another name if desired, but you’d need to change the command syntax to accommodate)
Launch the Terminal application, located in /Applications/Utilities/ folder and issue the following command:
Double-check the syntax in Terminal for accuracy, then hit the Return key and authenticate with the admin password when requested, this starts the Sierra boot drive creation process and it can take a while to complete
The command line will update with various messages and progress, when the “Done” message appears, the MacOS Sierra Boot installer drive has been created successfully
Quit out of Terminal as usual when finished
It can take a while to complete the creation of the USB install drive, depending on the speed of the USB interface and the drive itself, so just be patient.
Once finished, you are free to update an existing installation to MacOS Sierra using the installer drive, or you can reboot any target Mac and hold down the “Option” key to select the macOS Sierra 10.12 installer as a bootable installation volume. Be sure the Mac you are trying to update is compatible with MacOS Sierra otherwise the installation will fail.
Proceed with the installation of macOS Sierra as any other Mac OS X system software installation, just be sure you back up a Mac first if you have personal data worth preserving.
That’s all there is to it. We’ll cover how to dual boot macOS Sierra Beta and other Mac OS X versions shortly. Remember that beta releases of system software are intended for advanced users and preferably on a secondary machine, beta software is notoriously buggy and tends to underperform compared to a regular final release.
Any questions? Tell us about your experience making a bootable macOS Sierra install drive in the comments below.