Installing Windows XP from USB pen drive

I want to install Windows XP on my desktop computer (only XP), but my CD drive is not working.

I've only found installation tutorials on how to install it on the pen drive rather than from the pen drive.

How can I install Windows XP from a USB flash drive?

Answer

The easiest way:

WinToFlash starts a wizard that will help pull over the contents of a Windows installation CD or DVD and prepare the USB drive to become a bootable replacement for the optical drive.

WinToFlash is freeware and portable.