Outline the walkway with wooden stakes and string. Clear the area between the outline with a shovel, removing dirt and leveling the surface.
Put a subbase of compactible gravel down for the walkway. Walk on the gravel and pack it down until it is even.
Place two 2-by-4 wooden boards on their edges to form a wooden frame for the walkway. The inside edge of the form should line up with the strings. Drive wooden stakes on the outside of the form at 3-inch intervals and nail them to the form. Level the form with a carpentry level.
Place the flat rocks on top of the gravel at desired locations. Place them high so they won't be covered by the cement.
Spray form oil on the inside of the wooden forms for easy removal from the cement. Prepare the cement mix in a wheelbarrow with water.
Pour the cement and use a shovel to spread it over the walkway. Level the cement using another 2-by-4. Run the shovel along the inside edge of the wooden form and then hit the outside of the form with a hammer to settle the cement.
Smooth the cement surface using a wood float or finishing trowel. Sweep the surface of the cement with a wide push-broom to create a textured look and non-slip surface. Cover the walkway and let the cement set for about one week.
Remove the forms after the cement has set and fill in the sides of the walkway with dirt or sod.