I would like to advice you against it. When we summon this ?spirit?, we have no way of choosing good spirit from bad. And if a bad spirit (demon) answered your call, it?s very hard to get rid of them. They will haunt you and your family.
Demonic entities are very deceptive. They might be nice in the beginning. Sometimes they disguise themselves as your relatives or friends. And just when you start to trust them, they will gradually turn violent.
But if you still want to follow through in evocation, then here are some ways:
I would get a medium or if you are one yourself, then you already know how to.
see this page: