How do I get from zurich airport to bern central railway station?

I will be going to Switzerland for the first time and I will be landing at Zurich airport. I have seen that the airport has its own railway station but I can't seem to find any information about it. My destination is Bern Central Railway Station. How would I find the timetables? Are there trains at all times? How much would it approximately cost? Also, I'm only going to be in Bern for a week and then I'll be going back to Zurich Airport... Would it be advisable to get a travel card or would it not be worth the money? Thank you...