Hello rubiesmoon9 :) Best of wishes, luck and blessings on your goal at hand.
What is your current practice you are using? Seeing colours is a common experience, most report indigo.
My own experience happened naturally for myself. From what I have heard of other cases, when opened forcedly it can become dormant again, but there are loads of people who are impatient, thus there are loads of practices out there thankfully, to help open the third eye. Some think the ability to see auras and energies comes with the opening of the third eye.
It is but a form of consciousness as it is raised, as we grow spiritually, the chakras open naturally. There are the physical exercises. But the spiritual
work, the mental work, and personal revolution will help it along too. It is the same with forcing a kundalini awakening, forcing the dormant energies to rise upwards - it is after all a
spiritual awakening, and your spiritual progression should be in alignment, thus along with your practice, do not forget about working on your spiritual growth and personal work, it is very much entwined ;) The chakras are entwined as well, jumping to the third eye, without working on the lower ones
could effect the progress, if one chakra is healthy and radiant it blooms and heals the ones around it, also remember to remove any blockages, those things are pains when trying to work on chakras
Anyway, here is some of my experience: All my chakras are open - throughout my childhood my third eye was always slightly open, i was just
born that way, and i would experience a delightful tinging sensation throughout the pineal gland, and third eye area, I feel this chakra extending from the forehead, through the middle of the head, to the back of skull, and it has two openings. I was always a very insightful intuitive child with spiritual gifts, some just thought i was nuts! The third eye is thought to give people "psychic" talents. I wouldn't know as i've always had gifts, and third eye sensations for as long as i can remember.
It felt like a tickle, and the area was always very sensitive, it reacted to things being near it. It opened and felt raw and slightly painful with energy sources being nearby it, so sometimes when the third eye was asleep, all i would have to do is put my palm near my forehead. It became a major pain to deal with, as slight movements from blankets during the night would set it off. I had no idea what it was, i thought i just had some kind of human whisker sensors on my head.
Then my kundalini became active as soon as my third eye completely opened - it started at the third eye. The tingling sensation grew into these sharp vibrations, and i felt the pineal gland open completely, just like a bolt of lightning! At first i thought i was having some kind of brain seizures or nerve problems, went to the doctor and they had no idea what i was talking about. i experienced some unpleasant times. That's the whole reason i found this site back then, seeking answers to what was going on with me, i quickly learned, and my kundalini quickly spread too, like a wild fire. In a matter of a few days, the fire of kundalini spread up to my crown chakra, i could feel it expanding, thus it began traveling down my neck, and i always blocked it off from traveling down with physical impulses of cringing because it was so strong and almost painful feeling. These vibrations were unknown territory, thus i had to learn to relax through them, since then my kundalini has traveled all the way down, up, down, all over my body, out of my body, through all the chakras in my body not just the seven major ones, and does a lot of interesting and orgasmic feeling things. It is always awake in the crown now, crawling around, and i can control it's movements to go where i choose. It really is orgasmic and pleasant feeling after getting used to it.
The main thing for me, is i could feel it open physically, and i knew, there was no ignoring it.
I have learned to identify where all the chakras are automatically, and am able to hit the switch in my mind, and can pick out the many pathways they take to course along to the next, if i can simplify this, i guess you need to focus your brain onto the exact area, and eventually you will be able to connect the dots rapidly. Try to pin point where the third eye is, concentrate on it, it's easiest, because you can also stare up at it.
I've seen colours too. Also energies. And many things. Though i don't know if they relate to the third eye or not, as i have a lot going on spiritually. My favourite colour is this amazing golden light around that area.
Well, along with the third eye expanding, I experienced some unpleasant symptoms, such as nausea, disorientation, extreme sensitivity to energies, i could not go out in public for weeks because i could sense everyone, extreme fatigue, some migraines, and many other unexplainable symptoms which made me think i was either dying or getting sick, but this could also be from the kundalini awakening, this is not meant to sound negative, as it only lasted a few months, and the end result was amazing and more beautiful than anything i could imagine!
Hope some of my experience helps a bit, and good luck!