We can say that Installing Windows from USB is a hard job and there are rare people who are professional in this job. You have no need to achieve any such tweaking today, meanwhile there are hundreds of 3rd party instruments that can do the occupation. Here I’d like to say that now you are able to make use of the the well-known Windows 7 USB/DVD Tool from Microsoft to get a bootable DVD or USB device of Windows 8. so, below you can see a step by step guide to install Windows 8 from USB drive.
First of all downlaod Windows 7 USB/DVD Tool from here and install it, and then select the Windows 8 ISO file that downloaded file.
When you have done that, you should click USB device.
Now select the USB drive which you want to convert into bootable Windows 8 drive and click Begin copying and after some time your USB will be ready.
Now restart your PC and boot from USB drive to start installation procedure of Windows 8.