Call control is one of the most important skills when working as a customer service representative. You must apply your call control skills in a variety of scenarios, including when a customer is upset or when he wants to keep talking without getting to the point.
Glean as much information from the conversation as you can. Politely interrupt the customer if he is wandering off the subject. Wait until the customer pauses, then jump in quickly and take control of the call.
Allow an upset customer to vent. Interrupting an irate caller could upset her even more. Wait until the caller pauses before attempting to take control of the call. Apologize to the caller before asking any questions.
Use close-ended questions -- those that can be answered "yes" or "no" -- to reduce talk time when faced with a long-winded customer.
Answer any personal questions with a short answer, then quickly regain control of the call.
Stick to your scripts if you have one.