Download the required image
Using
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Download Rufus (preferably portable)
Launch Rufus.exe
USB device will be selected automatically, if not you can select it in the dropdown menu
Select disk file
Press start
Confirm disk erase
Using dd (Linux)
In terminal run:
lsblk to see all block devices, your USB drive will be /dev/sdX
sudo dd if=your_image.iso of=/dev/sdX bs=1M status=progress; sync
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Using Rufus (Windows)
Open rufus
Press on the select Button
Navigate to the .iso file
Press start
Press ok to confirm the write method (may be different for you) usually no need to change it:
Confirm destructive action
Wait until it finished and you are good to go