uh... okay, not too sure about most of that, but opening your third eye takes concentration mostly.
you could open all chakra's, or just the one, but i'd sudjest working on them all to some degree at least. meditate, then visualize in the middle of your forhead a violet light. there are many other ways to visualize, some see a violet flower opening, or a violet gem of some kind, or even a spinning disk. the point, whatever you invision [i see a gem in a violet haze, so we'll go with gem] it will be muted in colour, or dirty, visualize it getting clean, it could spin, or you could invision something wiping it away. as you practice, there will be less gunk to clean off and the colour will get brighter.
after the chakra work, you should strengthen it with psychic excerizes depending on what it is you want to do. it sort of sounds like something to do with seeing things most can't, so i'll go with aura's. you can use your own hand to do this, have it a bit away from a wall of a solid colour [i prefer dark colours, but others like lighter] stare slightly past your hand. as time goes on you will begin to see a thin line around your hand, and with further practice most see colour. [i don't, but i can see everyone aura with little effort]
there's also a third eye tea i know, but it's at home in my BOS and i'm at work currently. i believe there's one like it on the site, so you could search for it yourself. hope that helped.