A random stone path is a lovely way to add vintage appeal and a practical element to the garden—not only does it create a charming focal point for your yard, but walking on stones decreases dirt tracked into the house.
Consider where your path should lead (to a bench or special grouping of plants?) and whether it should be straight or meandering. Avoid getting too close to large trees (and their roots). Walk the course to see if it feels right, then lay out the path in 3-D using stakes and twine, or even a garden hose. Do some spots seem too high now? Would an adjustment right or left work better? Live with your mockup for a few days before installing.
Lay stones atop the grass along your route. Pay attention to how shapes fit together, overall appearance, and spacing between them—24" on center accommodates most strides, and 3' is a good standard width. (You want the path to be wide enough for two people to walk side by side.)
Once you’ve arranged the stones in a pleasing pattern, it’s time to install them. Start by cutting around the edge of the stone with a utility knife or a spade. Next, move the stone and cut laterally beneath the turf. Take a trowel and dig out some additional soil—your hole should be 1" deeper than your paving stone.
Place a ½" layer of soft sand into the hole, then compact it. The sand will help keep the stones from heaving. Finally, set the stones one at a time, checking for level as you go. Placing them ¼" below the surface of adjoining grass will allow for easy lawn mowing.