I don't.
I once attended a seance, just for fun, with some friends who believed.
We started to communicate with the "spirit" by asking them yes or no questions.
After some questions, we figured out the spirit was a girl who was apparently killed with a knife and now wandered in an abandoned barn nearby.
We asked if the killer was among us and she said yes.
At this point, everyone but me was really scared.
We asked if the killer was that guy (pointing at one of my friends) and she said no.
We asked if it was me, and she said YES!
My friends were sweaty and looked at me as if I was a real killer.
We asked if I would kill again that night, and the spirit said yes once again.
I was trying my best not to laugh, but everyone was scared shitless, one girl in particular.
We called it a night and went to sleep.
I slept well and of course I didn't kill anybody.
Next morning, when I woke up, I decided I would prank the scared girl, so I grabbed a huge butcher knife and waited for her.
As soon as she came downstairs I said "hello" with a creepy smile and the knife in my hand.
She shrieked and almost pissed her pants

but I couldn't hold my laugh so she realized I was joking after a second or so.
Yes, I know, it was an evil prank, but totally worth it.