Evaluate the highlights of the garden and determine how much access the walkway should provide. Sketch existing or planned flowerbeds, trees, any water features such as streams or ponds and respite areas for clearings, benches or tables and chairs.
Choose the type of stepping stone for the path. Bluestone, granite or travertine pavers make good stepping stones as do concrete pavers that can be shaped and colored to resemble natural stone.
Mark the walkway on the lawn with spray paint or small wood stakes and string. Measure precisely or roughly, depending on how unplanned you want your walk to appear. A narrow path should be about 2 ½ feet wide and a path wide enough for two to stroll will be about 4 feet wide. The distance between stones is about 18 inches, but this will vary if you design a random path.
Lay the stones down for a sense of how the finished walkway will look. Try out the stepping stone distances to be sure they are comfortable for a walker with an average stride. Push a sharp, flat-blade shovel into the ground to outline the stones.
Remove the stones and dig out the areas where they will go. Once you have removed the sod and the dirt, scatter a thin layer of sand -- an inch deep is fine -- in the hole to act as a stabilizing base so the stones will lay flat. Fit the stones back into their holes.
Check to see that the stones are level by placing a flat board over several of them at a time and setting a carpenter's level on the board. Adjust any stones that stick up or sink down too much. Fill in around the stones with loose soil and tamp it down firmly so the stones will stay in place. If you are adding ground cover, scatter seeds in the freshly dug dirt and water lightly to avoid shifting the stones.
Sweep dirt from the stones and let them settle for a week. Keep the seeded ground cover watered until it takes hold and surrounds the stones with Irish moss, sedum or another low, sturdy greenery. Ground cover will not need maintenance once it is rooted. Trim it back slightly if it begins to grow over the stepping stones. Alternatively, let the lawn fill in around the stepping stones without planting additional ground cover.