I had that talk with my daughter before that, and it was fairly level and adult in scope. I told her explicitly that there was never to be a Ouija board in the house, and she was not to engage in any type of conjuration, summoning, or communication inside. We have sufficient land that if she wanted to experiment, she could do so outside. From there it was an easy transition to my own experiences and experimentation when I was young, and she both grasped it immediately and subsequently had no issues abiding by the rules, since I explained to her the possible consequences and how it could affect the rest of us in the house.