Determine where to start the path. Open a tape measure slightly wider than the path's width and lock it into place. Lay it on the ground, where you want to start the path. Hammer wooden stakes into the ground to indicate the path's width.
Tie a long string to each of the wooden stakes, near the bottom. If you are making a straight path, extend the string about 10 feet toward the path's endpoint. Hammer another wooden stake into the ground at this location, wrap the string around the stake, and continue to extend it toward the endpoint. Stop every 10 feet to pound in another stake and wrap the string around it. If you are making a winding path, lay the string on the ground and use it to outline the path's shape. Measure the two strings' distance from each other every 4 to 5 feet to avoid making the path either narrower or wider.
Mark the ground under the string with spray paint.
Start to remove the grass at the beginning of the path. Hold a flat-edge shovel at a 30-degree angle to the ground. Push the shovel through the ground to cut about 1 to 2 feet underneath the sod.
Use the shovel's edge to cut through the sod and remove the chunk you loosened. Push the shovel underneath a second 1- to 2-foot section of sod and cut it free with the shovel's edge. As you remove the grass, keep the shovel as level as possible.
Continue to remove 1- to 2-foot sections of grass until all the grass between the spray paint lines has been removed.