1) A human’s DNA mixes with a werewolf’s.
He/she is bitten by a werewolf.
He/she is the child of at least one werewolf.
He/she eats a part of the werewolf.
He/she drinks water from the pawprint of a werewolf.
He/she drinks water downstream from where a werewolf is drinking.
2) In the case of Mental Shifting, there is no given way to become a werewolf. It just happens, being something of a genetic fluke.
3) A human cast a magic spell to become a werewolf.
