Formating laptop using my usb drive

Hello there...

I had a problem in format my friend laptop. The problem is my friend dvd rom was damage and I could not format her laptop using cd... But someone had told me that I could format the laptop using usb
( pendrive) that contain xp installer, but I don't know how to do that....
Could someone help me or give an instruction on how to format laptop using pendrif...

hello there ...thank you for your help...I had find the solution from your web suggestion... thanks a lot bro