Estimate the number of flagstones for a walkway by determining the approximate length and width of the pathway and multiplying the numbers to find the area. Contact the stone supplier who determines the number of flagstones the project requires from the area. Flagstone is a natural material that varies from 1 to 4 inches in thickness. Most suppliers sell it by the ton and each ton normally covers 80 to 100 square feet, depending on thickness.
Putting together a flagstone walkway is much like putting together a jigsaw puzzle in trial and error process. Generally, it is best to place two smaller flagstones by each larger stone. Prepare a gravel base for the walkway to ensure proper drainage and keep joints to less than 4 inches wide and adjust the gravel in the base so you ensure the stones are level. If a stone fits in the walkway but is too thick, use a hammer and chisel to split the stone or shape it to ensure the best fit. As you plan the walkway, walk on the stones to ensure they encourage a natural walking pace.
After situating the stones, fill the area between them with good quality top soil. Cut the sod you removed for installing the stones and plant grass between them. Keep the grass watered until it becomes well established, giving the new walkway a natural appearance.