Here's all you have to do to prevent psychic attack:
Say a prayer of protection. As you are saying the prayer, visualise a shower of the purest white light from heaven pouring over your whole being. (See it as either fine droplets of white light, or as a cleansing ray of light). Visualise this light filling your body, cleansing your body of darkness, and creating a barrier or capsule of impenetrable white light around you.
And that's it! Is that easy or what! Try and do this at least twice a day, perhaps once in the morning, and once in the evening. You can even white light yourself when you're out and about. If you're sitting on the bus or train on the way to work, or you're feeling stressed during the day, visualise the calming white light pouring over you. It may sound too simple to be true. But it DOES work. If you do this on a regular basis, your life WILL get better.
"What do you mean by a prayer of protection?" I hear some of you ask. I've included an example of a prayer that will ward off psychic attack...
In the name of Christ,
I ask for my Guides to come close to me.
I ask that a capsule of light be cast around me
to seal and protect me from any energies, entities or
influences that may be detrimental to me.
Fill my aura with the light and love of God,
And help to bring me closer to perfection each day.
Of course, feel free to use your own prayer, but be aware of one the elements of the prayer above. "In the name of Christ" is an essential part of the prayer because it immediately attracts the positivity of Christ towards you. If you are more comfortable with Kuan Yin, the Buddha, or other deity, use that. The important part is calling on your perception of purity and divinity.