Subject: Travel from Venice to Switzerland

Hello Ziners! I am new to this forum, and am happy to have a place where I can get personal travel advice. My husband and I are going to be in Italy and Switzerland in March. We fly in to Rome, and out of Zurich. I am wondering if you have any advice on how we can travel from Rome to Florence to Venice and then to Bern or Zurich most inexpensively (we have friends we are staying with in Bern). Thanks.