Employ a traditional letter format. It's time to quit the job, and you're not giving two weeks' notice.Here's how to politely write a resignation letter, effective immediately. The purpose of this message is to inform you that I am resigning my position at EvilCorp. Begin your letter with a statement of intent that is brief and focused. State that you are resigning and the effective date. How to write a resignation letter that's effective immediately? "A resignation letter should be short and to the point. Simply explain why you're leaving and the date of your departure. Taking into consideration the following points can help you avoid legal trouble and pick the right time to submit your resignation in Washington state.