Explain why you're leaving. Briefly explain the reasons you've decided to leave, both related to your current job and to your new position.A good resignation letter is a simple one. There is no real need to elaborate farther than you have to. Learn how to write a short notice resignation letter with this stepbystep guide, template and examples of formal resignation. Here's how to write a resignation letter when you're quitting for a job with a better compensation package, and you want to provide your employer with a reason. Professional resignation letter examples for different reasons. Free templates and writing guide to resign on a positive note without feeling awkward. Here are some reasons you may choose to resign: • Leaving a part-time job for an internship opportunity. • Changing career paths.