Here are some basics on how to build a wood fence.
1. Determine layout of posts and mark the ground. The easiest way to do this is to find your beginning and ending points and attach a landscape line to each so you have a nice straight line to follow. You'll also use this line to help you align the posts.
2. Dig holes for posts. Depending upon the size of the posts and your location (frost depth) you'll have to go deeper/wider than we did, but we made ours about 10" in diameter and 18" deep.
3. One by one, put the posts in the holes and fill in with concrete around the post. Bring each post up to the string line so that it's barely touching the line and then use your level to get it plumb.
A post level is a great time saver here because it determines plumb on two planes at once.
Brace each post using 2x4s. If you make the concrete stiff, you shouldn't have to fiddle too much with bracing. Periodically check the alignment of the posts with the string line by sighting down the line and making sure they all line up nicely.
4. Once the posts are in and the concrete is set (24 hours is best), it's time to assemble the fence. Our fence design was pretty simple - 1 2x6 positioned vertically fastened with 3" screws toenail style into the posts, 1 grooved 2x4 with groove up attached with pl premium and 3" screws to the 2x6, 1x8 slats dropped into the bottom 2x4 groove, and 1 grooved 2x4 with groove down fastened to posts with 3" screws and to slats with pl premium and a 1 1/2" screw every 2'.
5. The last step was to cut the top of the posts off to make them flush with the top of the fence.
6. Finish the fence with whatever product you want, or leave it as is and allow it to naturally weather