Just boot this CD file(ISO) and follow instructions.
Usually, just pressing return/enter should work, except maybe
pressing d to load drivers when it asks for that.

To make a bootable USB drive / key:

1. Copy all files from this CD onto the USB drive.
It cannot be in a subdirectory on the drive.
You do not need delete files already on the drive.
2. Install the bootloader:
On the USB drive, there should now be a file "syslinux.exe".
Run this from a command line, like this:

j:\syslinux.exe -ma j:

replace j with some other letter if your USB drive is on another
drive letter than j:
If it says nothing, it did install the bootloader.

Please note that you may have to adjust settings in your computers BIOS
setup to boot from USB.
Also, some BIOS (often older machines) simply won't boot from USB anyway.
Unfortunately, there are extremely many different versions of BIOS,
so I am unable to help you.

Been tested and found working (XP). Reported to be working on Vista as well. Share any details of this software if you use it.