Ok, here are some important things to consider before reading further; 
1. Everything
 is energy. Humans, animals, minerals, plants, thoughts, emotions. All 
aspects of existence, no matter what it is … is the same energy.
2. When energy impacts an environment, it changes it. For good or bad --- it will change it.
3. Everything
 has some form of consciousness. Everything is a ‘spirit’ thought form. 
Created by higher forces to exist in the form that it is; to function in
 the form that it is; to interact it the way that it does.
4. You are part of everything else. What affects one part, affects all other parts.
5. Like attracts like.
6. Cleansing is healing.
From
 the above, you should glean the importance of cleansing the energy 
fields which make up you and your environment. Although we might not 
always be able to sense an energy imbalance; we are nevertheless 
affected by it. Some areas/buildings feel comfortable to us, while 
others may make us feel edgy, depressed or anxious to get out.
After
 there has been a heated argument in a room for example, the atmosphere 
may feel heavy and dismal. You may even begin to feel irritable 
yourself. This negative energy, if allowed to exist and even grow (like 
attracts like), can adversely affect all the inhabitants in that area. 
In your house, it can even make you, your family, your pets and your 
plants sick. It will actually make your house sick. Animals are 
especially vulnerable as they act as buffers for us, and will absorb 
this negativity until they get physically sick.
When we cleanse, 
we're replacing undesirable energy (aka negativity) with desirable or 
positive energy. Anything can be cleansed and probably should be from 
time to time..
If you do a cleansing ritual or procedure with 
anger or fear of the negativity you are trying to release, you will only
 exchange one kind of negativity for another. You gain nothing. Always 
enter into any cleansing process with an attitude of love. Negative 
energy is not bad or evil; it is simply energy that does not sustain 
you. Nothing is inherently evil --- it is our judgement of it that 
labels something good or bad.
There are numerous cleansing methods available, but one which is particularly reliable is Smudging.
Smudging,
 (passing through smoke,) is an ancient method of cleansing that works 
quite well. I've used it to cleanse my house, and it's very good for 
smaller items and for cleansing your aura. When smudging a room, work in
 one direction, spiralling to the center. Which direction you use is up 
to you - try both. Counter clockwise is usually considered banishing; 
clockwise is invoking.
Use White Sage, but garden sage works equally 
well. Pine, of any kind, is generally thought to bring in desirable 
positive energy; while the sages are more for banishing the negative. 
Both can be used during the same smudging ritual. Use powdered sage or 
pine on charcoal, or a smudge stick or even a small wad of the leaves. 
Carry a heatproof container (ashtray) in the left hand; the smudge in 
the right.
For a room, try to start near, but not in front of the
 door, sweeping the smoke into all corners; up to the ceiling and down 
to the floor. If you use leaves or a smudge stick, knock the ashes off 
often, so you won't catch anything on fire. It's a good idea to keep a 
container of water close by, just in case.
Repeat the following, if you wish, during the smudging:
From the Element of Fire 
Comes this smoke, which is Air.
From the Element of Earth
Grows this plant, which is Water.
I call upon the Elements and the Blessings of Spirit
To please cleanse this (area, space, being, etc.)
For the good of all.
Continue
 until every inch of the area has been touched by the smoke and you it 
has been finished. As with any magickal rite, intent and visualisation 
are important. Visualising the movement of energy adds the power to the 
cleansing procedure.
