Watch this video from This Old House to learn how to lay a flagstone walkway.
1 Use a garden hose to lay out the shape and location of the 3-foot-wide walkway.
2 Cut through the sod and roots along the hose using a flat-blade shovel or edger.
3 Dig 3 to 4 inches of dirt from walkway.
4 If you encounter a thick root, cut it out with loppers.
5 Install steel edging along each side of the walkway.
6 Hold the edging in place with steel spikes.
7 Cut slots in a 2x4, spaced 3 feet apart, and slip it over the edging to maintain the correct walkway width; install one spacer every 8 feet or so.
8 Cover bottom of excavated walkway with filter fabric.
9 Spread 4-inch layer of pea stone over the fabric; rake it smooth.
10 Lay flagstone onto the pea stone, making sure the best-looking side is facing up.
11 Press the flagstone into the pea stone, then tap it with a rubber mallet.
12 Continue setting flagstones, while maintaining consistent spaces between them.