To write a short notice resignation letter, include your position and effective date, explain your reason and express gratitude. State that you wish to quit and include your final day of work.I will go over a step-by-step resignation template letter you can use, how to structure it and provide examples of resignation letters. Dear (name of manager),. Due to unforeseen circumstances, I must resign from my position effective immediately. Learn how to write a professional resignation letter with our step-by-step guide, easy to use templates and helpful tips.