On a paper business letter, you often include the CC line underneath your signature, either above or below any enclosures line. Here are the various abbreviations you can use to note carbon copy on printed business letters: cc: c.c.
Under your name at the end of the letter, skip two lines. On the third line, write "Enclosure:" or "Enclosures:" if there are multiple documents. Skip a line after "Enclosures:" and then begin your list of enclosures. Put each enclosed document title on its own line.
Type “Enclosure” and the name of the enclosed document under your signature. If you've included an additional document to your letter or email, place an enclosure notation beneath your signature. Write or type “Enclosure” followed by the name of the document or content attached.
Formally, you would refer to the enclosed items in the body of your letter followed by (enclosed) and then, under the signature at the end of the letter you'd write "Enclosures (x)" where x is the number of enclosures.