I bought a Windows 8.1 upgrade key, just checking on how to put it on a USB flash drive

Kilo7-

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Nov 4, 2013
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So I built a new PC the other day and needed an OS. I have W7 on this current PC I am typing on right now. I want 8.1 on my new PC for better speeds, so I bought an upgrade key that (yes, it is valid, and is 100% legal) is in my email.

http://www.microsoft.com/en-us/software-recovery

^Since my new PC has no optical drive, I need to install W8 via usb flash drive. Do I just insert my W8 key into the link above? Do I need the W8 disc? I have the W7 disc, but thats useless probably. Where do I go after putting in my key into the link?