How to Burn DMG to USBby Stephen A. Powell ; Updated September 28, 2017
Creating disk image files allows you to preserve discs, drives, applications and large folders in their entirety for transport, sharing and future use. While you may have used your Apple computer's inset Disk Utility to burn a DMG file to your computer in the past, you may not have known that you can write the disk image directly to a USB storage drive.
Copy all of the files you wish to burn to the DMG into a single folder or volume if you have not already done so.
Launch Disk Utility from the Applications folder.
Select the disk or volume from which you intend to burn the DMG from the list in the left pane.
Select "New" from the File menu.
Choose "Disk Image from Folder" or "Disk Image from disk name" if you want to burn a DMG of a directory or drive, respectively.
Name the DMG file in the appropriate field.
Select the connected USB drive from the file destination browser.
Select the DMG format from the ensuing pop-up menu. Choose from compressed, read only, read/write and DVD/CD master.