Yes its a sin. I used to be heavy in the occult: I read a book from the psychic Sylvia Brown, was into astrology and numerology, astral projection( thank God that never happened), crystal and indigo children, reincarnation.... man it was a lot... But in short, don't do it..its a gateway for the devil... I remember the bible saying to stone all doctors in the old testement.. But all of it makes no sense, when God knows you more than any psychic ever could seeing as he made you...and 12 signs couldn't possibly encompass the personalities of trillion of people that have lived, are living and will live... Its madness, and now I realize that, and I hope you do too.