The following are the things to keep in mind when writing an immediate resignation letter: Write the date first. Explain only necessities.Learn how to write a short notice resignation letter with this stepbystep guide, template and examples of formal resignation. An employee absent for two or more scheduled work days without notice, permission or without good reason will be considered as having resigned. a. When providing a reason, keep it brief. No need to get into the specifics. Learn how to write a professional resignation letter with our step-by-step guide, easy to use templates and helpful tips. A resignation letter should be brief and to the point, usually no more than one page. No need to install the app. What Skills Should I Put On My Resume?