Taylor discusses 6 key aspects of writing a resignation letter, including when to give notice, what to say, how to format it, and how to deliver it. I regretfully have to inform you that, after much thought, I have decided to resign and please accept this letter as a formal notice of my resignation."Learn the essential steps and tips for writing a professional two weeks notice resignation letter. Use a formal business format. The most common format is block format. Is an unsigned resignation letter or an email resignation legally acceptable in the state of Michigan? A resignation letter should be short and to the point. Simply explain why you're leaving and the date of your departure. Is an unsigned resignation letter or an email resignation legally acceptable in the state of Michigan? Now that you're in the body of the email, you want to make it abundantly clear that you're resigning.