Outline the edges of the area in which you’d like to install the flagstones, using small stakes connected with twine to form a “fence.” Tap the stakes into place with a rubber mallet.
Excavate the grass and plants in the area using a shovel or edger. Remove turf and cut deep roots using a lopper.
Rake the bare soil so it is smooth. Remove any loose stones.
Cover the raked area with a generous, even layer of powdered granite, and tamp it down with a hand tamper.
Ensure the granite surface is level (for drainage) using a level; build up or scoop down areas as needed. Re-tamp before placing flagstones.
Lay down flagstones. Wear the safety goggles if you need to chisel stones to break into smaller pieces to fit together. If you will be planting moss between the stones, leave a 1-inch gap between each stone.
Tamp down the stones, and remove the stakes and twine.