Seances ARE usually 安全 and 你 can either use a ouija board 或者 go to a professional who will perform it with you.
The easiest way to go is with a Ouija board-all 你 do is get in a circle, ask a question, put your hands on the mover thing, and it will spell out the answer letter-by-letter.
If 你 want 更多 in-depth:
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