My convocation ceremony is next week and I am super nervous. I've watched the video McMaster made for the steps of the actual ceremony (getting your ticket, lining up, giving your name card, etc.) BUT it does not touch on where you go once you cross the stage! Do you just go back to your seat? How do you know where to sit?

Anyone with experience or who has been to a convocation pleaseeeeee help calm my nerves :(

It kinda seems to be like the Kipling ceremony.

So basically you listen to the obligatory "bla bla bla.... new minds... bla bla bla.... our future...." speech, like you hear in every major student event. Maybe some presentations for parents (investors), then some speech from the students. That will take over an hour, and only after the people who own the university stop stroking their ego you move on to graduation. By the way you are gonna stand for all that time, so get your comfy shoes. Then you have to stand for several hours waiting for your turn to get to get the thing.

In short it's basically: stand for 4 hours, the end.

I heard that the Science Convocation is apparently 4.5 hours of just standing, getting your degree with thousands of people in the hall and taking a few pictures. Doesn't seem too exciting....

Don't worry about where to go, they have people directing you and unless you're literally the first person to graduate at the entire convocation (unlikely unless you're getting a PhD and last name starts with A or B), you get to watch others do it first.
Everybody else is in the same situation as you, so just relax. They've organized hundreds of these.