Mark your walk outline with stakes and mason's twine. Use a tape measure to measure the correct width of the walk and use a line level to level the line at just above the height for the finished walkway.
Excavate the path with a shovel and rake it smooth. Dig the path to about 6 inches deep. Spread a layer of gravel over the bed and compact it with a hand tamper.
Outline the walkway using plastic or metal edging, sunk into the ground even with the planned walkway, or use bricks for an outline by setting them at a different angle than the main walk. Pick a style for the walkway -- running bond with each brick overlapping neighbors by half a length, herringbone with the end of one brick set against the side of the next or basket weave with two or three bricks set one way, then two or three others set perpendicular.
Pour a concrete base for a mortared brick walkway by setting 2-by-4-inch boards on either side of the walk, securing them with stakes on the outside. Compact the gravel inside the forms and pour 2 to 4 inches of concrete over it.
Smooth the concrete by dragging a board over it inside the form. Make it fairly level, but leave final leveling to the mortaring. Spread a layer of mortar over the cured concrete with a trowel and set bricks into it, pushing them down firmly and leveling them with a level. Put mortar on the sides of the bricks before setting them in place. Clean excess mortar off with a trowel.
Lay a sand base for a mortared brick walkway by spreading 2 inches of sand over the compacted gravel. Level it by dragging a board across it between the edging material. Place bricks in the sand base in the desired pattern, leaving 1/2-inch between bricks on all sides. Level the bricks with a level. Sweep dry mortar into the gaps once all bricks are set, making multiple passes until all gaps are filled to the top. Spray water over the walkway with a sprayer or misting nozzle on a garden hose to harden the mortar.