Generate a guide explaining the 'Worry Time' technique. The guide should instruct the user to set aside a specific, limited time each day (e.g., 15 minutes) to intentionally think about their worries. It should explain how this practice helps contain anxiety and prevent it from taking over the whole day. The tone should be clear and strategic. Please include a disclaimer that this is a CBT technique and may be best used with a therapist's guidance.