Here is the Short video on how you can create usb bootable MacOS Sierra installer disk for mac os Sierra 10.12.
Steps
1.Open App Store
2.Download Mac Os Sierra
3.Take 8Gb and Above USB and Format it and Rename it
4.Download MacDaddy from below link
5.Select Destination USB and Location of MacOS Sierra (Application Folder)
6.Click Create Installer it may take 15-30 Mins
7.Once you get confirmation message the USB is ready to use
Bootable MacOS Sierra 10.12
Install Mac OS Sierra from usb
USB startup disk
MacOS Sierra Flash Drive
mac os x recovery disk download
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Apps for Creating Bootable USB for mac.
http://macdaddy.io/install-disk-creator/
http://diskmakerx.com/
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