In the top left hand corner of the envelope, you'll need to include your name, street address, city, state, and zip code. We'll detail everything you need to know about how to invite a guest speaker, from the earliest planning stages to drafting a formal speaker invitation letter.Organising a conference and need to invite a speaker? Click here for a free download of our invitation letter to customise. On behalf of the XYZ and the XYZ Organizing Committee, we are honored to invite you to speak at the XYZ event celebrating Cybersecurity Career Week (CCW). Dear Passionate Seeker of Speech,. Your invitation should be a formal email (or letter). Outline the reasons why you've chosen them as the best person to speak at your event. A graduation invitation is different from a graduation announcement. Discover considerations, best practices, and essential elements of a wellstructured speaker invitation letter.