Click on the Disk Utility option to run it. Navigate to the following pathway: Application> Utilities> Disk Utility.
Once the DMG is burnt, the USB drive, now bootable can be used as an installer on any other mac System. The in-built disk utility on Mac is ideal for burning DMG to USB. This method may vary depending on which Mac OS version you are currently running, but the overall concept is same for all. Burn DMG to USB on Windows using PowerISO Burn DMG to USB on Windows using UltraDMG Convert DMG to ISO First then Burn to USB