This guide is now obsolete and has been superseded by Download Windows 10 Version 1903 and Create a Bootable USB in Windows or Linux which instructs with the newer Build of Windows 10 and also addresses a common error found with Unetbootin.
You need a Windows 10 Installation .iso to download the latest version see Windows OEM Downloads and FAQs. Note avoid using the Windows 10 Version 1809 ISO Downloaded by Direct Links has an install.wim which exceeds 4 GB. This means your Bootable USB won't pass Secure Boot.
Please use the Windows 10 Version 1903 (Build 18343) ISO which is more stable than Windows 10 Version 1809 and doesn't have this issue. Note use Windows Update immediately after installing Windows 10 Insider Preview 18343 as this will upgrade to the Windows 10 Version 1903 Mainstream Build.
This guide will also work for a Linux Installation .iso, Parted Magic Installation .iso if the Bootable USB is to be created within the Windows Operating System.
If you are running Windows opposed to Linux see my Guide Creating a Windows 10 Bootable USB for a UEFI BIOS within Windows.
Downloading and Installing Unetbootin
We need to install a program called Unetbootin in order to create the Bootable USB. Open up FireFox and search for Unetbootin:
Go to the Unetbootin home page:
Then select Download (Linux):
You will be given three commands to install Unetbootin:
To the top left select Activities:
Then search for Terminal and launch it:
Copy and paste the first command into the terminal:
Then press [Enter]. You will then need to input your password into the terminal in order to give it root permissions to install software:
Press [Enter] to confirm that you want to install Unetbootin:
This first step will be done:
Now you need to proceed with the second line, copy and paste it into the terminal:
Then pres [Enter]:
Now copy and paste the third line into the terminal:
Press [Enter] to continue:
Press y to continue:
Unetbootin is now installed:
Insert your USB flash drive and open up Activities to the top left and search for Disks. Open Disks:
You will find your USB Flash drive to the left. In my case it is a 16 GB USB flash Drive. Looking at the additional details I can see that it is connected to /dev/sdb1:
Go to all Applications:
Scroll down and select Unetbootin:
Unetbootin will warn that it must be run as root. On the error message copy and paste the command:
Then paste it into the Terminal (Do not press [Enter] just yet):
Close the error message
Close down Unetbootin:
Press [Enter] to launch it from the Terminal:
Unetbootin will now be ran with root permissions:
To the bottom check that the Type is USB Flash Drive and that the Device matches your USB Flash Drive. In my case /dev/sdb1:
Next load the .iso:
Then select your .iso file:
Then select Ok:
It will then create the Bootable USB
When it is finished select the [Exit] button:
You now have your Windows 10 Bootable USB. You can have a look at it by opening up Files to the left hand side:
Then select USB:
The select USB:
It's contents should look like above.
You can use it to perform a clean install. For more details see Windows OEM FAQs and Downloads.