We advise our clients to schedule one to two buffer blocks in their calendars each day. Buffer blocks are 30 to 60 minutes in length, and they are used to get the emails, phone messages, and other routine tasks done efficiently. Buffer blocks reduce the time it takes to get all of the incoming and administrative tasks done and they keep those tasks from interrupting the more important things.
If you decide to try buffer blocks, let your contacts know when you have them each day so that they know when they can reach you. You might even change your voice mail to say something like "I am not available right now, but if you leave a message I return calls between 11 to 12 and 4 to 5 each day." Even if just 60% of your callers leave messages, you will be way ahead!
Brian Moran - 12 Week Year