What do you do when outside is -20c? (Zurich)

Hello

I will be in Zurich around Jan 6th- Jan 10th. Just received an interesting news from a friend over there, Switzerland won’t be too much warmer than Canada....So I am wondering as a tourist in winter, what should I do where should I go to appreciate the beauty and spirit of this lovely city?

I know Ski is one of the choices, but rather than that, what are the local secret to keep the energy high when the temperature drop to -20c.

Just want to see people out and up to do things. Hopefully it won’t like many people here to choose hibernating when the temperature drops or all packed it up on the ski hills. I am interested more diverse things to do over there in winter.

Please suggest, and many thanks in advance.

Yuan