In the opening paragraph, clearly state that you are resigning from your position. Resignation letters should use the formal greeting: "Dear".The first sentence in the letter should state that you are resigning and when. This article will cover some pointers for writing a flawless resignation letter for graduate studies. Well technically you're doing this in pursuit of better job opportunities. Just say you are resigning with the effective date. I hope this letter finds you well. For those in more traditionally professional fields such as law, finance or politics a formal resignation letter may be more appropriate. Add contact details, company name, and date. Use business letter format.