When you are digging the post holes, simply use a standard post hole digger tool. At each stake marker, dig the hole to the depth that you'll need in order to bury one-third of the post. When you are placing the posts into the holes, you can anchor them with more sturdiness if you have dug the post holes a little bit wider at the bottom than at the top.

Place a couple of shovels full of dirt or a large stone at the bottom of each post hole, so that you allow for drainage and protect the posts from rotting. You'll also want to have stained the bottom third of every post with a wood preservative before placing it. Put this stain on a full 24 hours before you are going to place a post in the ground.

When you have put a post in the ground, you need to pack it. You can use either concrete or dirt for post packing. Put three shovels of whichever gravel you choose into the post hole before setting the post in place. Once a post is in place, use a level to check and make sure that it is in a perfect upright position, no leaning. Also do a “sight-line” check with your naked eye.

Once a post is correctly aligned, brace it with a stake. If you are using concrete for your packing, leave the bracing stake in place until you are certain that the concrete has dried. If you are using dirt, then once you know that a post is correctly aligned you need to thoroughly tamp it to make sure it's packed tightly. It's important that you take care not to alter the fence post's alignment with your tamping.

Once a post is firmly into its position, you will want to build a low mound of concrete around it so as to protect it against standing water. Slope the mound away from the post at an acute angle and use a trowel to smooth it off and make it rounded. Tamp the mound lightly to get rid of any air bubbles which could trap water.