Keep your communications to the point. If a recipient is paying for access by the hour, he or she won't appreciate messages that take forever to read. Thread your messages when appropriate.
Threads are a series of responses to an original message.
Assume your e-mail is private. A general rule of thumb is to keep your signature file down to 4-6 lines. To find out more about netiquette, visit the free online version of Virginia Shea's book Netiquette .