To serve the Tribunal, you have to personally take the filed petition and affidavit to the Tribunal’s office and give the documents to a secretary, clerk, or agent of the Tribunal. Make sure that you write down the date, time and the name of the person you gave the documents to.
If you do not live near an office of the Tribunal, you can arrange for someone else to serve the documents for you. This person will have to be able to provide an affidavit of service. See the section Proving Service for more information on the affidavit of service.
You should include a cover letter with the documents that you are serving.
This is a blank service letter that you can download and fill in: Blank Service Letter
This is a sample service letter that you can look at as an example: Sample Service Letter