By car you travel up the A9 to Caithness. It's a fantastic journey north through the heart of the highlands. Beyond Inverness the road begins to hug the east coast and there are some fantastic views to enjoy as you drive northwards through the villages of Dornoch with it's cathedral, Golspie and Dunbeath.
The train journey north beyond Inverness is equally interesting with some great vistas over the unspoilt northern highlands. There are plenty of trains from the south to Inverness. You then need to change for the journey north to Thurso. You can then catch a taxi to Scarfskerry.
By air you have the choice of flying to Inverness and then hiring a car or getting a train or bus north. The other option is to fly to Wick via Edinburgh or Aberdeen. This is a bit pricier than Inverness but gets you closer.