Usb to IDe adding a operating system?

i have a dell desktop that needs a operating system i took out the hard drive and im hooking it up to my laptop with a usb to IDE cable. i dont have a recovery disc for my dell desktop i have a oprating sytem on my computer so i was just going to add the operating system from my laptop anybody have any good stregeys on doing this anyone haves any steps.. and i cant even put a disc in my dell computer or anyhting because it doesnt have a operating system so keep that in mind when answering please dont feel like seeing any sarcastic answers please..