Create macOS High Sierra Bootable USB Installer on Windows 10

Firstly, you need to download TransMac application as we will use this to write files onto flash drive. Once you have downloaded and installed TransMac, run the application.
TransMac is a Paid Application. But the trial period will last for 15 days, this is more than enough for us to Create Bootable USB Installer for macOS High Sierra Windows 10.
Before you click Run, just make sure you have plugged-in your 16 GB USB Flash Drive.
Now, Click Run and proceed with the trial of 15 Days. You should see the following screen once you click Run.

Right-Click on your USB Flash Drive and select the option Format Disk for Mac.
When the warning pops-up click Yes.
TransMac will now ask you to name your ISB Drive. I will name my USB Drive as “USB Installer“, but you can name it anything you like. After you Name the USB Drive click OK.

Click Yes, when TransMac will give you the Overwrite warning.

Now, just wait for few moments, as the formatting process is going on.

Once the formatting is successfully completed you should get this following confirmation. If it is not a success, please follow the steps again and format your flash drive.
Click Ok, and now right-click on your USB Flash Drive again and select the option Restore with Disk Image.
Click Yes, when TransMac gives you a warning for Overwriting.

Next Step is to Select the dmg file for macOS High Sierra. You would need an Mac to download the macOS High Sierra Installation file from Apple Store.
To locate the DMG File, follow these steps
After you have downloaded the High Sierra app, locate the InstallESD.DMG from the installer.

In Applications folder: Right-click on Install MacOS High Sierra app, then choose Show Packages Contents to reveal Contents folder.

The MacOS High Sierra InstallESD.DMG is found under: Contents/SharedSupport/

Now copy this InstallESD.DMG as you need it in TransMac to Create macOS High Sierra Bootable USB Installer on Windows 10.

Ok, so lets continue with TransMac Restore Disk Image to Drive. On this screen, select the InstallESD.DMG file and click OK.
Click Yes, when TransMac Gives you the Overwrite warning.
Now the TransMac will start the process of Restoring High Sierra Image on the Flash Drive.  this will take 15-25 minutes, depending on the speed of your flash drive.

Ok that should be it for this tutorial on How to Create macOS High Sierra Bootable USB Installer on Windows 10 PC.