With the head.
Then there is the wonderful PATERNOSTER:
http://www.hamburg-oben-unten.de/
It is sadly going out of style in Germany, but these elevators have no door and run continuously. As the box you want to enter (up or down) comes, you step in - quickly - and when you get to the floor you want - you step out quickly.
Very efficient, really cool to ride in but kinda scary the first couple of times.
I was trying to look up an alleged fatality at the Halls of Residence at my uni’ in Northern Ireland but all the google links lead to terrorist killings cos they wouldn’t “lift” a threat against someone :rolleyes: