Prepare to spend the best part of 3 hours there 😁
We got there at 7, was already a line of 3-400 people, around 7:45 they began letting people in. In the hallways there are multiple rooms for family where you can sit and listen to the ceremony over speakers.
Ceremony itself - I counted 22 rows of 45 people for mine, they wait for it to be full and then the ceremony begins.
Oh, be prepared to applaud for every country represented, we had to clap 86 times.
After that, there's a large outdoors area you can use for photos that's just outside where family and friends can sit.