Please maintain a copy of the letter in the employee's work site file folder. The employee's work site folder must be kept at the location for one year.Employee shall send a written notification to the supervisor at least 2 weeks in advance of resignation. 2. In this article, we share tips for writing a short, simple resignation letter and offer examples for you to reference when creating your own. You probably won't have to, but some companies do require a formal letter, so you'll have to check with HR as to whether you need to write one. Add contact details, company name, and date. Implement resignation from MiamiDade County Public Schools (resignation letter attached);. 4. Title: Letter of Resignation. Mail a letter or complete and send in an Information. I already sumitted my resignation letter and don't even have another job.