Lay out the plan for your fence either by staking or painting lines on the ground. If staking, drive small wooden stakes into the ground 4 feet apart on your fence plan at at each corner. Start at one corner and tie string around the stakes to outline where you want the fence.
Call the utility company and have someone come out to mark off where there are underground utility lines. Adjust your fence plans as necessary to avoid these underground lines.
Hold the post hole diggers over the area where you are planning to install a fence post. Hold the handles close together. Raise up the post hole diggers, and then thrust down to stab the diggers into the ground.
Spread the handles of the post hole diggers apart to operate the digging mechanism. Lift up with the handles spread apart and move the diggers to one side of the hole. Press the handles back together to open the diggers and release the soil.
Repeat the thrusting of the diggers into the hole and pulling the diggers out to remove soil. Dig holes that are 1/3 deep as the total length of your fence posts. Repeat the process for each fence post you require.