The eight sided pattern, called the bagua, is what I use to practice feng shui in my home. It actually has nine sections if you count the center. It is depicted traditionally as an octagon with pie shaped sections. But you can also depict it as a rectangle with nine equal spaced squares, three on all sides.
You line up the bagua on the floor plan of your home, with the bottom of the pattern aligned with the wall that contains your front door. If your door is in the center of the wall, you will enter your home via the career section of the bagua. If it is one the left of the wall, you are in the knowledge or contemplation area. On the right, and you enter through helpful people.
Then you see what parts of your house are found in each section of the bagua, and the fun begins when you intuitively rearrange each section, moving things attentive to the specific realms.