Here are the steps to create a bootable USB drive:1. Insert your USB drive into one USB port on your computer
2. Click "Start" at the bottom left on your computer screen
3. Type "cmd" in RUN window to open a command prompt
4. Type "disk part" into the command prompt and press Enter. After that type "list disk" and press Enter again.
5. Determine which of the list of disks that display which is a USB drive. (For example, 4GB USB drive, then the option with 4GB size that's all you see). Record the number that identifies your USB drive it on paper.
6. Type the following command into a command prompt to format on a USB drive.
"Select the disk A," replace "A" with the number you get in step 5 earlier. Press Enter"Clean." Press Enter"Create Partition Memory." Press "Enter.""Select Partition A." Press "Enter.""Format FS = NTFS." Press "Enter.""Assign." Press "Enter.""Exit." Press "Enter."
7. Insert the installation CD of Windows XP or Vista you. Your computer will read the installation CD, and a window will appear on the screen. List of all the existing drive will be displayed there. Look for the letters which is a symbol of the CD-ROM and USB drive. Take note of these letters in the paper.
8. Type the following command into a command prompt:
"B: CD boot," replace "B" with the letter which is the symbol of the CD-ROM. Press "Enter.""CD boot." Press "Enter.""Bootsect.exe/NT60 C:," replace "C" with the letter which is the symbol of the USB Drive. Press "Enter."
9. Copy the boot information from the installation CD to USB drive by entering the following command into a command prompt:"Xcopy c: *.* / s / e / f B: /," replace "B" with the letter which is the symbol of the CD-ROM and replace the "C" with the letter which is the symbol of the USB drive. Press "Enter."
Let the computer to copy the data from the installation CD to USB drive.
10. Unplug the USB drive from the USB port, replace the lid, and give the label "bootable" with a marker. Save the USB drive it in a safe place. Remove your Windows installation CD and return it to its place.