Measure out the area for your flagstone walkway and use wood posts with string tied along the outside to mark the border.
Call your city's building department and find out if you need any special permits or licenses before you begin building.
Call your utility provider and ask them to come to your house to check for any underground wiring that would prohibit digging.
Excavate the entire digging area that you measured out with a shovel.
Compact the surface of the soil down using a hand tamper.
Line the inner border of your walkway with two-by-fours cut to the length and width of the area. Attach the two-by-fours to each other using screws.
Pour a 2-inch layer of gravel into the hole and use a hand tamper to compact the gravel down tightly.
Mix the cement according to the package instructions and pour a 3-inch layer of concrete over the entire gravel base.
Use a shovel to spread the concrete around and ensure the concrete is filled in thoroughly.
Level the concrete out by dragging a two-by-four across the top surface several times until it's flat and even.
Allow the concrete 24 hours to dry.
Mix the mortar according to the package instructions and pour a 1-inch layer of mortar on top of the concrete base, enough for one flagstone at a time.
Use a trowel to spread the mortar into an even 1-inch layer.
Place the flagstones on top of the mortar one at a time, starting in any corner of the walkway.
Pound each flagstone tightly into place with a rubber hammer.
Allow the mortar 24 hours to dry.
Mix the sanded grout according to instructions and use a grout sponge to spread it around and into the spaces between each of the flagstones.
Let the grout dry for 12 hours and clean the surface of the flagstones before using.