Shetland is located 200 miles North of Scotland and also 200 miles west of Norway. Shetland is made up of 100 Island with 16 being inhabited all year around.
To get to Shetland, fly from Edinburgh, Aberdeen, Glasgow and Inverness to Sumburgh Airport in Shetland.
https://www.loganair.co.uk/
Daily flights leave from Sumburgh Airport located at the south end of the Island to Aberdeen, Edinburgh, Glasgow and Inverness.
When you arrive in Shetland there is a bus service from the airport into Lerwick. There are also car hire companies located at the airport should you wish to hire a vehicle.
https://www.boltscarhire.co.uk/
http://www.starrentacar.co.uk/
https://www.northlinkferries.co.uk/
The main ferry service between Aberdeen and Shetland runs daily. It takes about 12 hours always on a direct overnight sailing.
The boat has lovely cabins and reclining chairs, so it’s very comfortable. If it is not a direct sailing, you will be calling into Kirkwall in Orkney as part of your journey.