You can find parking at Kilry school during holidays. Walk across the Burn of Kilry past the Standing Stone cottage and a wee path leads to the stone.
Set amongst the trees this is a beautiful place with the Knock Of Formal providing a wonderful backdrop. Add a touch of snow and frost and the atmosphere totally changes.
A good place to spend a bit of time being quiet to soak in the surroundings.
From Alyth take the B954 north until the road forks, signposted for Dykehead and Kilry. Follow this un-numbered road until you see Kilry School, a small building. There is a little cottage opposite, appropriately named "Standing Stone". There's not much in the way of parking here, and the road is very narrow. The stone is to the north side of the cottage down a private track - please ask before entering. It sits in a peaceful glade in the trees, and on the map, appears to be perfectly aligned with the Pitmudie Stone Row and the Auldallan Stones. You can't see any one from the others, but try it on the map with a ruler.... Spooky! I'll leave discussion of this coincidence to the believers in ley lines, etcetera.