If you are planning on visiting Switzerland you should have a valid passport. Residents of the following countries do not need a visa to travel to Switzerland; Andorra, Monaco, San Marino, Australia, New Zealand, South Africa, Canada and the USA. For European Union residents you should have a certificate of EU country.
If you are an Asian national then you need a visa. In most cases a visa can be valid for three months, but with time the period can be changed to a few years. For more details you can ask for assistance at a Swiss embassy in your area.