In summer time (after the 21st of June) it is possible to get there on a ferry with the help of Veteran Fjordcruise AS . That's why before this time you can only drive. If you use GPS devices be aware of getting lost and alway control the way it shows you. It is better to print the road description from internet and insert the road sections step by step.
You will for sure need trekking shoes in order not to break legs and warm jacket. It is also necessary to take water and some food with you.