You can open your third eye through meditation. It is recommended that you open your chakras from the bottom and up starting with your root chakra. If you just choose to open your third eye, there are physical and mental side effects that be from tired to becoming emotional. The chakras work best when they are all open and are balanced.
Try to search the forums on articles containing channeling spiritis.
There are no spells for this as it deals with energy working.
Re: increase clairvoyancy
By: Lumpino Jan 14, 2015
Post # 9
For opening a chakra is necessary years meditation on one chakra only.
But, by my opinion is much better then Third eye - chakra Ajna - opening chakra Anahata.
This path is outlined in book The secret of the golden flower, translantion by Richard Willhelm. Is free on net.
About three months meditation on chakra Ajna (in this book a Heavenly heart) and then a years meditation on Anahata, until is chakra open. Meditation on chakra Anahata you could done in common life too, and before you sleep. By this way is possible accelerate result. But on Anahata only. On Ajna not.