For instance, "Dear Jane" before announcing your resignation. 2. I regret to inform you that, after much thought, I have decided to resign.Please accept this letter as a formal notice of my resignation. Include the last date of your employment in your email. Provide your employer with as much notice of your resignation as possible. Learn how to write a resignation letter with a notice period. Established an official notice of resignation from your job title and state your last day of employment. This article covers everything you need to know about writing a personal reason resignation letter, when to write it and how much detail to include.