Why's she talking about "red carpet?"

Rebecca

She is referring to the long red carpet laid on the ground for special guests to walk on when arriving at an event or place. It's commonly associated with Hollywood events. It's mentioned here because she is saying that these types of events often begin during the daytime, out in the open. Ex: The supermodel walked the red carpet at the Met Gala. Ex: I had a red carpet for my wedding guests. It made them feel special.