I am an ex-international student (Spain) and I have the experience of drafting official letters to the embassy for the purpose of securing student visas. I have an extensive network of students, a good number of which is already in Canada who I can connect with for additional information regarding the Canadian embassy.
The main elements of any student visa application, which I will employ in your cover letter as well are as follows: your background, your course and school details, your intent behind the studies, what you plan for future after your course. All these details are necessary to convey authenticity in your profile and will guarantee a successful application. Please feel free to inbox me for any clarification.