If you are writing a letter of intent for a business then there a few things you need to keep in mind. You may start your letter by mentioning your name, address, email address and contact number on the top left corner.
Traders are better off NOT using documents like LOI, ICPO, FCO, etc. Even if and when they rarely are used in internal trades, on a restricted level within specific industries, they have no legal or customary basis in International Trade whatsoever. In fact the presence of many of these terms are considered to be signs of Advance Fee Fraud, by knowledgeable players and law enforcement.