From the South
Head north out of Glasgow on the A81 towards Milngavie. Stay on this road through Strathblane and Blanefield. 
A mile outside Blanefield, you will pass the Dumgoyne Distillery on your right. 
Ignore the next right signposted for Killearn and carry on, passing the Beech Tree Inn on your left. 
1 mile further on, turn right at the large roundabout heading up the hill into Killearn. Take the second left - opposite the postbox - into Gartness Road. 
Firfield is the last house on the left hand side heading down the hill.