Well, as you probably know, meditation is quite helpful. There are some wonderful tracks on YouTube that you can listen to while meditating to get into a deeper trance. Searching "meditation," "meditation music," or "third eye music" brings up some good results, from my experience.
There are also some meditation exercises you can do to open the third eye (or open it more, in your case). A common one I've seen is chanting "Thoth" while meditating.
The color purple is associated with psychic abilities, so burning purple candles while meditating or doing a ritual for developing your abilities might be in order. Along the same lines, amethyst is also associated with such things. Charge an amethyst crystal to keep on your nightstand or under your pillow, carry one, or wear one as an amulet.
Frankincense and jasmine incense are both used for spiritual and psychic rituals.
Speaking about empathy exclusively for a moment: I've developed my empathic abilities by studying people. Try to feel what people's emotions are consciously; really think about it. Ask people how they are and try to feel if they're lying. Since you are able to communicate with the spirits of the dead, try to feel their emotions whenever you talk to them. (From my experience, the dead tend to be more emotionally raw, so it's easier to pick up on them.)