Climate in Switzerland depends on elevation and region, but is usually temperate. In mosy of the  major cities summer daily temperature average is 77 degrees F (25 degrees C). While winter average temperature is 27 to 32 degrees F (-3 to 0 degrees C). Winter in Switzerlnad tend to be long and snowy, especially in Alphes.

So if you going to travel to Switzerland in summer time, you would want to pack sun screen, shorts, T-Shirt, swimsuit (if you want to swim), some glasses. And if you want to visit Swiitzerland in winter time just get some warm stuff to wear.