Make a list of any additional documentation that you plan to include with the letter, along with the names of any contributors to the letter, whether they are writers or typists.
Note the initials of any contributors to the letter at the end. List the writer's initials in all capitals, followed by a slash and the typist's initials in lowercase.
Below the initials, note any enclosures with a notation like Enc., Encs., or Enclosure: (the name of the documents). If you have more than one document, add the number of documents in parenthesis after the notification. This would appear as Enc. (2), for example.