Guernsey's roads are narrow — many are single-track with passing places — and the island has a maximum speed limit of 35 mph. If you hire a car, get a small one and take the collision damage waiver seriously. A public bus service circles the island and is a pleasant way to see the coast without the stress of driving. The full circuit takes about 90 minutes.
Walking and cycling are practical for the southern parishes. The cliff paths along the south coast are some of the best walking on the island.