Things You'll Need
Dry-cut diamond blade and circular saw
Building a set of outdoor rock steps in your backyard landscape allows for a rustic aesthetic while serving a functional purpose. Building outdoor rock steps does not require complex and specialized masonry skills. If you have basic carpentry skills, use simple materials such as wall stone and flat flagstones, and have the proper tools, building outdoor steps with rock can be relatively easy. Build the steps in the portions of your backyard that feature a natural rise.
Make a rough outline of your rock steps, using spray paint to mark the soil in your selected location. Drive stakes at the top and bottom of your staircase in the center of the horizontal lines.
Calculate the rise and run of your steps. Tie a level string line from the top stake to the bottom stake. Measure the distance between the stakes along the level line to determine the run--the total horizontal distance the stairs must cover. Determine the rise by measuring from the ground up to the level line.
Calculate the number of steps for the staircase by dividing the rise by 6 inches. This gives you the number of risers you'll need. To get the number of step treads, subtract 1 from the number of risers. Steps should be 6 to 8 inches high and approximately 12 inches deep, according to The Family Handyman.
Calculate the depth of each tread by dividing the total run by the number of treads. Mark the location for each tread on the ground with spray paint, according to the tread's dimensions.
Purchase stones of the correct dimensions for your stairs. Purchase wall stones that measure 6 to 8 inches thick for the risers, and flagstones that are 2 to 3 inches thick. Purchase 15 percent more stones than necessary to allow for more shape options.
Dig a trench a few inches deep to create the first step. Set in a wall stone to act as a riser. Leave enough of the riser showing above the trench so when it's combined with the flagstone tread, it equals the correct rise measurement. Dig a flat surface out from the back of the riser to form the surface where you'll place the first tread and the second riser stone.
Place the first flagstone tread so it overhangs the riser. Fill in the depth of the first tread with smaller flagstones that fill the space. Repeat this process to add more risers and tread stones to build your steps.
Cut away 16-inch sections of sod lining your steps so you can shape the yard to the form of the steps. Round the dirt ledges and shape the steps' surroundings. Replace the sod and water it. Fill the cracks between the tread flagstones with a 50-50 mixture of soil and compost.
You may have to cut some flagstones so they fit together to form the shape of each tread. Make the cuts with a circular saw and a dry-cut diamond blade.