Are reservations preferable? (Since it's a Michelin Restaurant)

Go early and stand in line. It's part of the experience.

The best thing to do is arrive when they open and put your name down or maybe get seated immediately.

You have to show up in person when they open to make a reservation for that evening. Arrive at least 15 mins before they open - there will be a line. Then you will get the option to eat immediately or choose a later dinner and come back.

Reservations are only allowed for parties of 6-12 people.

For sure.