Well if you really want to mess with your friend I suggest setting up your own RAT(Remote Administration Tool), and infected your friends computer, and then you will be able to do anything to him. Since your new to this, I suggest going here
You must login or register to view this content.. They have tons of tutorials on how to set them up, and how to use them. It will take some time for you to get use to it, but you will catch on fast, it's not hard
. Good luck.