bad ideas. but ill help. im good at concocting tortures and shit...
go to his house while hes sleeping, break in through the window to his room and hide in his room somewhere preferrably the closet. then when he wakes up he will see that all his clothes are on the floor from his closet (you throw his shit from closet to floor duh) then hes like wtf is happening...then he sees that his dog is dead in his hallway with its limbs scattered throughout his room and on his bed(you obviously kill dog and mutilate ftw

) then hes freakin now...so then thats when you pop out of his closet and take a syringe filled with heroin (AIDS infected needle btw) and stab him in the jugular artery.
he will become addicted to heroin and develop the aids virus so hes bound to die. just make sure you dont leave evidence or youre fucked.
the whole closet thing is so you can psychologically fuck him up. like brain fuck him.
start whispering shit when hes sleeping to wake him and then start whispering scary shit about how his parents are gonna die and how you raped them both and then came to his house to do the same to him.
also, you could find out if he has any phobias...
clostropobic?
saran wrap his entire house closed and fill his room with packaging supplies and dead animals.
be creative! yay!