First time travel to Switzerland during May..some concerns

Switzerland in general is "a bit expensive" although there is a range of options, including hostels. Upon arrival in Zurich, don't sleep there but push on to either Luzern or the Berner Oberland area. I would want to stay in a couple of different destinations, to minimize backtracking, then probably sleep in Zurich on just the last night before your flight home.

Swiss trains generally don't need reservations, but if you want a reservation for a special scenic route, such as a "panorama" car on the portion of the Golden Pass line between Zweisimmen and Montreux, then you can reserve at a train station there, with either a pass or a ticket. Instead of the 4-day flexipass version of the Swiss Travel Pass (about $305 US), I would be more likely to lean toward the more comprehensive version for 8 consecutive days (at $387), but it will be easier to decide the more your travel plan comes together. Passes and tickets are both sold there at Zurich airport train station.

Do pack light, so that you can manage luggage in a variety of situations. However, for travel within Switzerland, you can also check luggage through their [Fast Baggage service], turning it in before 9 a.m. and picking up after 6 p.m. at many train stations.

Thanks Laura for the reply.

We are planning to go to Lucerne from Zurich, and from there to other places. I will include Berner Oberland also in the itinerary. As you mentioned, 8 consecutive days pass would have been better if we had that many days with us. We have only 6 days including the date of departure. How about 4 days consecutive pass? or flexi pass? Can we select the route as we wish or do we need to stick to the routes mentioned in the site when we apply for pass?

Thanks

Depending on the weather there may be mud or snow in the Berner Oberland that early in the season. Just be prepared for less than perfect walking conditions.

This map shows routes where a Swiss Pass is valid.
http://www.sbb.ch/content/dam/sbb/de/pdf/freizeit-ferien/ferien-kurztrips-schweiz/internationale-gaeste/sts-geltungsbereich.pdf
That is pretty much every populated village on the rails. Mountain railways and lifts that only go to tourist sites such as view points, restaurants, trail heads give a 25% to 50% discount. They are marked on the map.
If you have a Swiss Pass, you just board the train and show your pass when asked by a conductor, with a few exceptions like EC trains and special tourist trains like the Glacier Express and the Bernina Express. The tourist trains require a paid reservation.

I would recommend a stop in Lucerne, as we were there about a month ago, a 2-day respite between the trains from Paris to Florence.

Beautiful town, nice people, great food, not unbelievably expensive although a little pricey. Lake Lucerne and the Reuss River with the panorama of the Alps all around are fantastic scenery indeed.

Stayed at Hotel Walstatterhof right across the street from the train station, a nice room & facility for ~200 CHF per night. That's about as reasonable a price as you'll probably get for something so close to the station.

To put it mildly, the Berner Oberland is not at it's best in early May. As popular as the region is on this website, most people's perceptions of it is based on their experiences in the summer. It's a completely different ballgame in the spring. Usually quite muddy, wet and overcast, and a lot of the tourist infrastructure goes on temporary hiatus between the ski and hiking seasons. And then there's the issue of the "fertilzer" the farmers spread on the pastures during this time when most tourists stay away. Do you like the smell of freshly sowed manure?

With only seven days in Switzerland, the Berner Oberland is just too low yield in early May to justify both the expense in money and your valuable vacation time. Save it for the summer or the winter ski season, and allocate your time elsewhere.

Tom's answer is worth reading twice for anyone thinking the Berner Oberland is going to be great in early May.