How do the mind reading illusions work?

Well, if the illusion includes cards it's basically a card trick rather than a mind reading trick but when it comes to pure mind reading it'really hard to maintain the illusion. Some magicians use stooges, others learn how to read your facial features, gestures and stuff and that's how they read your mind which is really hard to learn. It takes a lot of time. Some magicians use manipulation, they do certain things and based on these things your brain thinks about certain things and that's another secret. There could be some other ways too.