There are several other ways how to get there...
The easiest first
This bus takes you from town .....take this bus to Kilmacanogue and the bus will drop you off just under the hill of Sugarloaf. Make sure you ask the driver. You can just climb up the hill and enjoy the spectacular view.
This is link the map of the walk
After you get to the top you can walk down to Kilamacanogue village, just follow the tracks.
You can take bus n. 145 back....Timetable
Very easy to do
Make sure you have good shoes.