Upvote:1
Your best option will be a 4 day Swiss Flexi Pass (http://www.swisspasses.com/railpass/flexi/) with the optional Half-fare Card. This will cover Zurich to Luino (Day 1), Luino to Geneva (Day 2), Geneva to Sigriswil (Day 3). Half-Fare travel from Sigriswil to Jungfraujoch and back, Sigriswil to Zurich (Day 4). You would then get 50% travel from Zurich HB to the airport.