In an ideal world, we would live in a house that has perfect Feng Shui. In practice this is near impossible to achieve as we are not able to completely control the internal and external environment.
The best thing to do if you suffer from a serious affliction is to move to another place. However if the afflictions are not so serious or you simply cannot move then you can apply Feng Shui cures to soften the impact..
Let's say that your house is located at the intersection of a busy 'T' or 'Y' junction is exposed to 'killing' or 'sha' energies. The cure would be to build a structure like a high wall fence between the road and the home to block off the 'sha'. This is an example of a cure by blocking.
Some masters will recommend placing a shinny metal plate to reflect the killing 'sha' qi. This is an example of a Feng Shui cure by reflecting or deflecting.
Suppose that your main door is directly facing a lamp post. You can relocate your main door or change the direction so that it does not face the lamp post. This is a feng shui cure by avoiding.
Let's move into the house. Suppose the dining area of your house sits in a sector that is afflicted by the inauspicious earth energy of 2 and 5 that relates to illness and misfortune. Let's also suppose that you cannot use any other area for dining. What can you do?
In the study of Feng Shui, we know that one qi can affect another. For example in the exhaustive cycle of the Five Elements, metal can reduce earth qi. In this situation, I would recommend having metal in the dining area. This may be in the form of a old grandfather clock with a large metal pendulum that chimes.
Lets suppose that your main door sits in a sector that has the metal stars 6 and 7 during a period where the star 7 is inauspicious. I would normally recommend moving the door because 6 and 7 is associated with robbery accidents (in the current period of 8)..
But let's say that the door cannot be relocated. I would recommend placing a bowl of still water next to the door. Why? In the cycle of the Five Elements, metal produce water. In the process of producing water the metal energy is exhausted. Placing water exhaust the inauspicious metal energy. This is a example of a Feng Shui cure using the Five Elements.