We cannot provide any kind of in-depth preparation for your hearing. Going to similar hearings would be the best way to prepare if you have time for that. The Landlord and Tenant Board offers a publication that provides an overview of the hearing process, https://tribunalsontario.ca/ltb/brochures-videos/.  For information on how to submit evidence visit-https://tribunalsontario.ca/documents/ltb/Practice%20Directions/Practice%20Direction%20on%20Evidence.html#filetype.