Best way to see Switzerland for 4 days before going to Italy

Where does your tour begin? Then you can work backward--train if in the north and likely a flight if headed south.
Is it four nights?
Have you scoped out flights from your town to Geneva and Zurich?

What is your tour date and where does it start? That will make a difference in suggested routes.

When I want to see The Alps, I go to Western Austria--to Tirol. It's easier to travel there, and much less expensive. The sights are about same--about as beautiful as mountains get. Within 15 minutes through the Brenner Pass, you are in Italy.

We begin the tour at Lake Como on Sept. 27.
We would like to see some of Switzerland before going to Italy.
We haven't decided which airport to land at and are looking for advice.

OK. You have lots of options, depending on how much ground you want to cover and how many times you want to change hotels. I will describe a few:

Option 1). Moving each day: Fly into Geneva, take the train directly to Montreux and overnight there. Book a hotel near or with a view of the lake (Lake Geneva/Lac Leman) is you like. Experience a bit of Suisse Romande, the French-speaking area of Switzerland. Visit Chateau de Chillon

Day 2 take the train on the scenic Golden Pass route to Interlaken Ost, changing there to ride the short distance to Lauterbrunnen. Book a hotel in the valley or in one of the high mountain villages (Wengen or Muerren).

Day 3 take the rest of the scenic Golden Pass route to Luzern for your overnight. Stay in a hotel with a view of the river and the famous Chapel Bridge.

Day 4: take the train to Milan over the scenic Gotthard Pass route (change trains at Bellinzona to reach Milan). Change there for your train to your village on Lago di Como (Lecco or Varenna).

Option 2: 2 locations, 2 hotels:

2A). Fly to Geneva, take the train to Montreux for one night, then take the Golden Pass route to Interlaken Ost and thence to Lauterbrunnen. Spend 2 nights in one of the alpine villages. Day 4 take the train via Spiez on the fast route to Milan using the Lötschberg and Simplon tunnels. Change trains in Milan to reach your village. OR

2B). Fly into Zurich take the train straight to Luzern for an overnight there, then proceed to Interlaken/Lauterbrunnen for 2 night in an alpine village, and take the fast train to Milan as above.

2C). Fly into Zurich, go straight to Interlaken and Lauterbrunnen, spend 2 nights in your alpine village. Day 3 head to Luzern for one night. Day 4 take the scenic Gotthard Pass route to Milan, etc. (change trains in Bellinzona).

Option 3: One base: take your pick (Luzern, alpine villages, or Lac Leman) and spend all 3 nights there.

They all involve different amounts of time on trains, and different costs, so you will have to look those up and decide.

I will add another option.
Fly into Zurich and take a train to Luzern. Stay 2 nights.
Take the Voralpen Express to Pfaeffikon, then change to train to Chur, then a train to Samedan, then short train to Pontresina. Stay 2 nights.
Take a train to Tirano, Italy over the Bernina Pass. At Tirano, walk across the piazza to the Nord station and take a train to Varenna-Esino, where the tour starts.

A full day in Luzern will give you a chance to take a lake cruise with a stop at Viznau to take the Rigi Bahn to the top of the mountain.

The Bernina route is an excellent option as well; one we have enjoyed on our way to Venice.

I meant to put that in, but got interrupted in my posting by an urgent call from my husband to help out in the garden. And then I forgot about it. I am glad Sam added it.

It's relatively easy, there are 2 airports to speak of in CH - Geneva and Zurich. Zurich is the main one and further to the east, so closer to Italy.

Take Bernina Express to the Lake District after training around in CH. Or start in Geneva and work your way east and then south. Use Rick's book to decide how to spend your 4 days (bring lots of money).