Hi Robert,
Citizens of Canada do not need a visa to enter Mexico. You only need two things:
The first is your Canadian Passport, which has to have at least six months validity (from your arrival date in Mexico) left on it to cover your maximum 180 day stay in the country.
The second is a Mexican tourist card. It’s called an FMM (Forma Migratoria Múltiple) and used to be issued on your flight (if flying into Mexico) before landing.
Recently, this has changed and now you must apply online and print the form, which you can get here.
The same applies if you’re entering Mexico via a land border.
The FMM form is mandatory for all travelers entering Mexico from all other countries, including Canada. It will allow you entry into Mexico and a stay of up to 180 days.
The FMM has two sections. Both with identical information: name, nationality, date of birth etc. Fill them both in. One section will be retained at the border crossing or customs, the other section you need to keep. You’ll need this second section to leave Mexico after your stay.
Once you get through customs or across the border, keep the second half of the FMM with your passport, so there is no problem when leaving the country at the end of your stay.