Some gateways also limit the size of mail they accept. If your message is longer than about 20K, you might consider posting a short abstract and invite interested readers to request the complete version from you. You might also want to consider splitting the posting into several parts. If you have a longer post of general, longer term interest, contact the List Owner to see if it can be archived on the file server so people can request it. Use a descriptive subject line .
Many people decide whether they want to read a message based on the content of the subject line.
Sign all your messages. It helps to have at least a name to associate with a post and some mailers strip off the header, so the receiver cannot reply unless there is some kind of internal address. Be tolerant of newcomers . We were all new to this medium at one time, we are all still learning, and procedures are still being refined. Without a uniform standard, most subscribers will not be able to decode them.