BOOTABLE PENDRIVE

We can see pendrive is empty.

Copying windows xp os extracted files in to pendrive(USB Drive (F:)
Now copying files in to the pendrive.

After copying we can see some space has been taken by the files. 

After that restart the system in boot settings we have to change options.
Select boot and in that specify boot device priority as Removable drive and press F10 to save the changes then click on Y to save.

Now we can see 8GB option as pendrive click on it. 

We can see windows xp starts installing.