Oddly enough I was working on a telephone message template yesterday which would be virtually identical to this requirement. I have filled in the basics (see attached), but you will probably need to make some changes, particularly to the content control lists and the message format/recipients etc.
You can do the former easily with
Insert Content Control Add-In. The rest should be obvious.
Note you cannot include the slashes in a date used for the filename.
The process saves the document as a temporary PDF file which is added to the message as an attachment.