First you contact the university professors directly through email. make sure that the research area they do actually interests you and they have enough fund coming in their way to pay you. you send an email and ask for one to one conversation if you are in Toronto or live close to the location. if you are overseas, you can keep having those conversations over email. Academics are pretty responsive to their emails although you should be persistent and show you go out of your way to contact them. You talk directly with your research supervisor either through email or in person if you are in Toronto

Need to meet with professor and have interview one on one, need to provide proven experience with research and teaching. If referred by another professor then it would be a lot easier