Super confusing airport. If you are unfamiliar with this airport, my best tip of advice is to ask questions to every security officer/employee to make sure if you are going the right direction. This airport lacks a lot of signs pointing you to the correct direction and can be a nightmare mid-day when you are trying to catch a connecting flight.
My flight arrived an hour late and getting through customs looked like a nightmare. It was a good thing I still had an extra two hours to spare to make it through customs and go through security again. I ended up having just enough time to grab a bite to eat and drink before heading towards my gate.
Pro tip which should be applied to every airport, but especially Toronto: make sure you're getting screened for security for the right set of gates!