Windows 8 on a USB?

I just recently built my first PC, and I didn't purchase an Optical Drive. I was thinking that all I needed to do was open a folder and copy windows 8 onto a flash drive but that doesn't work.  Please Help

you need windows 7 usb/dvd tool from microsoft, to create a bootable windows 8 usb stick. the tool is free to download from microsoft.

Here is a tutorial. google is your friend.

http://pcsupport.about.com/od/windows-8/a/install-windows-8-usb.htm

It's kinda easy. The program does everything, you just need to select the windows image file and start. Don't forget to make bios changes if you want it to boot from usb.