1) Subject Line.
You can use a variety of subject lines. However, I suggest using something simple along the lines of “Great speaking with you” or “Thank you – Admin Assistant Interview.”
Your greeting will depend largely on the position you are applying for and the culture of the company. If you are unsure what to use “Good Day Mr. Smith” is always a safe bet. However, as I mentioned, different company cultures may permit less formal greetings such as “Good day John” or even “Hi John,” in extremely informal company cultures.
3) Main body
This is the most important section for obvious reasons. You are going to want to cover a few points in this section such as thanking them for their time and reaffirming your interest in the position. I recommend that you personalize this section by mentioning something specific from your interview.
4) Closing paragraph
Your closing paragraph does not need to be exceptionally long. Simply mention that you are available for any follow up questions and that you look forward to their decision.