1. Use the "Send a Private Message" link, which allows brands to move a public complaint into a private setting where a resolution can be achieved as details can be communicated more freely. Plus, of course, negative sentiment is discussed in a closed environment.
2. Be proactive by sharing any updates that will impact users - especially useful if there is a separate handle for operations, customer service, etc., since these Tweets will not interfere with brand messaging from the main account.
3. Answer simple questions, quickly.
4. Include hours of operation for Twitter accounts.
5. Follow up.
6. Sign the customer tweets.
7. Reply to other brand mentions too.
8. Be transparent.
9. Go the extra mile.
10. Speak their language.
Whatever approach a brand takes to customer service on Twitter, the strategy should include treating the network as an inbound channel as well as an outbound one. Spend some time visiting your favorite brands on Twitter and check out their "Tweets & Replies." This section of their profile will give you a good idea of how they are approaching customer service. If this section doesn't include any responses to customers, there are likely dozens, hundreds or thousands (depending on the brand size) of messages that have gone un-responded to and as many customers who will take their business elsewhere.