Hi, get your text edit message up, when finished, click "save as" from the top bar menu, and give it a name.
Then, open your AOL mail and write your introduction message and then you need to click on the icon that allows you to "add attachment" and navigate to the saved text edit file and choose it and then it will upload to your email as an attachment and then send the mail.
Otherwise copy and paste whatever you have written in text edit directly into your email.