Although we can't see them, waves of energy are literally passing through us all the time. Light waves penetrate our bodies, and radio waves are wherever we go, carrying information we are unaware of.
A clairvoyant has the ability to tap into a signal - similar to that from a TV transmitter - and see images that are hidden from others.
Many of us channel thoughts that seem to come from external sources. Whether we believe they come from God, from dead relatives or elsewhere, they often come out of the blue.
A clairvoyant will open themselves up to be a receiver, ready to accept messages from an external source.
People who are aware of having psychic abilities regard them as a gift, and work to develop their faculties. Clairvoyants will tap into the third eye chakra which is located between one's eyebrows. It is a gate that leads to higher consciousness, and allows the person to observe that which is hidden.
According to traditions of Theosophy, the third eye is connected to the pineal gland in the brain. This is regarded as having mystical and metaphysical properties, with Rene Descartes having described it as "the principal seat of the soul".
Concentrating on the third eye, according to many clairvoyants, clears the mind and opens up a pathway for external messages. This can be enhanced in a number of ways, including by sitting in a relaxed position and breathing deeply to release stresses and tensions.
Some clairvoyants will sit on the floor, placing lit candles around them. They often use crystals to amplify the psychic energies, and will find a spot away from such distractions as TV, pets and children.
Just as the five "recognised" senses are strongly linked - you won't taste your food if you hold your nose, for example - it is important to use them to enhance your sixth sense.
Sounds - perhaps relaxing string music - the aroma of scented candles, and soft lighting will all serve to help a clairvoyant tap into their psychic abilities.
It is important to rid oneself of negative emotions which work on low vibrations, and open up to receiving high vibrations to receive clairvoyant images.
One of the keys to seeing with the mind is to allow the mind to relax, clearing and opening the chakras. Relaxation techniques which often work include mentally counting down from 10 to one, increasing the body's vibrations with each step.
The forces and energies which can enter us are not all positive, so clairvoyants learn to only allow their guides or higher vibrational beings to communicate with them while blocking out those that can harm them.