Sorry I am just chiming in a bit late but maybe I can help. I have created several USB Ubuntu Linux flash drives. I use them to do things to Windows that I can't get done in Windows which is another story.

This article gives steps on how to do it. Windows 10 has it's own special issues when it comes to booting from the USB drive but the article discusses how to get around them.

http://dailylinuxuser.com/2015/11/ho...usb-drive.html

Post back with questions.

Lisa