Depends how you mean. If you mean where it comes from, I take energy from the environment and my own emotions and control them with force of will. If you mean how does it work? Mostly I shape the spells with time, practice, experience, and determination- except for Thaumaturgy, which basically enhances the effect using symbols to channel your power, or ritual magic, which borrows power from somebody else. I never did much ritual magic.
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