The rules for Wild Magic Surge are:

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> Immediately after you cast a sorcerer spell of 1st level or higher, the DM can have you roll a d20. If you roll a 1, roll on the Wild Magic Surge table to create a random magical effect.
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Are there any guidelines for how often this should happen? The player wants to roll for every spell cast, but the storyteller dislikes wild magic and hasn't had the player roll a surge yet.