This tutorial will teach you Windows 8 USB Installation. Screenshots are given to ease users. All you need is a usb flash drive of atleast 4GBand Windows 8 Pro iso file.
Windows-8-USB-Drive

Steps for Windows 8 USB Installation

First of all Download this program. This is Microsoft genuine tool to make usb drive bootable

download button
After you have downloaded above Windows 8 USB tool. Now follow below steps.
Open this tool from your programs.
Windows 8 USB Installation

Then Click on Browse button and go to path where your windows 8 iso file is located. If you haven’t download windows 8 then you candownload windows 8 Pro.
Windows 8 USB Installation
Click on WIndows 8 iso file and click on Open button.
Windows 8 USB Installation

Now from options click on USB Device.
Windows 8 USB Installation
From Drop Down box select your USB Pen drive letter e.g. H: or I: or G: and then click Begin copying. After the process is completed the USB is now bootable.
Turn off your computer and plugin USB. Now Turn on PC and boot from USB. Done.
If you have any issues with this tutorial then please comment here. I have also written the tutorial to install windows 7 from usb.