Installing windows 8.1 with usb

Hi all, building my new pc tomorrow, would like to know how to install windows through usb because I have no disk drive for my new build, I have the product code and a 16 gb usb stick, I have looked at tutorials but I would like some more advice because they have all been a bit conveluted or confusing.

Thanks.

http://windows.microsoft.com/en-us/windows-8/create-reset-refresh-media

Follow the instructions there. 

Then take your USB drive and plug it into your new PC and power it on. Some may automatically boot into the USB drive others you may need to select it. Spam delete or escape or whatever depending on your motherboard or go into the BIOS/UEFI and select the USB drive as your boot device. The computer will then start and the Windows Installer will begin. Then just click next a few times and you'll be set. 

cheers man