You walk in yo the bottom floor of the building and then they have signs and security to guide you to the right spot. You wait in a hallway with an employee who welcomes you and helps you on the elevator with others. Its a very easy process.
When I was there, a security guard was with us, filled the elevator to it's maximum capacity and took us to the 95 floor. So ask a security guard first.
Via a controlled entrance of the building before being ushered into the elevator.
Make sure when you enter into the main lobby you state to the employees weither you are going to the bar/lounge, reservations, or private event.
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