I'm not a Satanist, I'm protestant but EpicFail is actually right, although I disagree with worshipping yourself or thinking your the best person in the world(Mostly out of self-opinion, even though Pride is also a sin it's just more of a convient rule that I follow, hell I only follow like 60% of the Bible, mostly big ones I agree with like Murder, Pride, Greed etc. Because I mostly believe we're here for the simple purpose of working to make life better for others and we shouldn't think of ourselves in that matter, for every productive life, makes a positive world.) Satanism is not worshipping Satan, it is instead worshipping yourself, but there are Satanistic cults that do rituals for Satan etc. but it is not Satanism, it's just dumbasses worshipping a being that isn't as big as they think, since God overpowers him in every aspect of life, if Satan tried to takeover or destroy the world it would be of God's doings because according to the Bible, he knew that Satan would betray him and he knew that he would be sent the deepest pits of hell for it. Which means he also knows his plans, his plots and to anyone in a Satanistic Cult, he KNOWS you are in one.
I'm also 40% Agnostic.