What a beautiful walkway! This is going to be a very high maintenance project to maintain. The stepping stones need to be set on several inches of sand that has been compacted. The lawn should be squares of sod that you cut to fit. The sod needs to sit on a four to six inch layer of topsoil. Then you will need to hand cut the lawn squares with scissors or a hand trimmer. Maybe you can use a string trimmer? The practical way to do this would be to use artificial turf instead of real grass. Looks really cool but just a lot of maintenance. Keep growing, Marianne Binetti