Remember that what you post will be received by thousands of people throughout the world. Try to educate and be educated. In particular, if you ask a question, you should send a summary of the responses to the list, thus allowing others to learn along with you. The VERY important part of your posting is the Subject field. Your message will be rejected without it.
People screen incoming e-mail by the subject line, so make it clear.
Some people check e-mail on slower modems, often at home in the evening, so please be considerate. Send your longer file to the administrator instead. It will be placed in the CCL archives, and you only need to post a pointer and a description. It will be distributed automatically to all subscribers. You will also receive the confirmation message.