Many people reach John O’Groats by foot, bike, car or even by ferry from the Orkneys. Still, there is the possibility to got there by bus. Two bus lines running several times a day (services are less frequent on Saturdays, no services on Sundays) link John O’Groats with the next larger towns, Wick and Thurso. They stop at all the settlements in between, which means that the otherwise short journey seems to last for eternity. Still, it is a convenient way to get to John O’Groats without an own vehicle. Check out the timetable for line 77 (to/from Wick) or line 80 (Thurso) at Stagecoach Highlands. The bus stop at John O’Groats is just at the parking lot.
This is by far the cheapest way to get to Orkney. There are organised bus tours around Orkney.
I think it took about an hour (give&take 15 mins)
If you want to take your own car there's a car ferry from Thurso but it is very epensive.