How To Write A Patronage Letter . Leave two blank lines after the date. Dear mary, please accept this letter as notice of my resignation as a. 4 Different Types of Business Letters hennessy events from www.hegnessevents.com Make the purpose of your letter clear. Write out the recipient's full name, title (if applicable), company name, and address in that order, with each piece of information on a separate line. Begin with a friendly opening, then quickly transition into the purpose of your letter.