Just minutes after the train departs, your car attendant will come through and pour Champagne. Best way to start the journey.
By the way, each car has its own 24/7 attendant. All you have to do is ring the bell, and he or she will be at your service in a minute.
Your luggage has already been placed carefully in the cabin before you even step on board.
The attendant will bring you any food you want to order off your room menu (including a selection of Champagne bottles that goes up to 400 Euro). They'll also convert your space to sleeping arrangements while you're at dinner and will wake you up (at your desired time) with breakfast.