Confidence In writing an official letter, you should demonstrate confidence in yourself, in your message in addition to in your reader. It is possible to also write into the embassy for official answers they're pretty responsive and you ought to be able to receive your answers within a working day. So long as the letter includes all the essential info, you or the man inviting you are not going to have trouble writing it. Briefly note the key points that you want to highlight in the letter. The letter shouldn't be more than 1 page long. It must be in a formal language because it will address a formal institution, the German Embassy.