Have you noticed recurring emails from your customer? If you have it is time for you to start writing templates. This will eliminate the need of rewriting email messages for common questions. This will also come handy when one of your customer support team is OFF as someone else can easily take on this role.
On Amazon this email template feature is part of the Buyer-Seller Messages tool, which you can access by clicking the Messages link in the top right-hand corner of your seller account home page.