First learn about what the rules are for where you live and then you will be able to start thinking about the fence designs along with the height, material used and the placement of fencing. When it comes to the material, go with pressure treated wood so that is it termite and decay resistant. Fences that are six feet in height, then you need to have fence posts that are at least two feet deep. Have your gate posts and the end posts to be at least three feet in depth in order to give ultimate safety and security.