Your subconscious is like water, it takes the lead and form of whatever the conscious mind believes it is. So when you are deep in trance, and want a spirit guide, the subconscious forms one and has it come to you. This mechanism is how chakras work, indeed all forms of spirituality and mysticism.
So any kind of meditation will bring you closer to your subconscious. Any sort of thoughts you have, will be read by the subconscious. And you can read any kind of experience that you have, as a response from the subconscious. If you work hard enough at this, then you can have actual conversations with the subconscious.
At one point in the past, I communicated with my subconscious through a technique called the muscle test. This video illustrates the process I used:
I noticed that my mind would have little reactions right before I performed the test. After enough focus on these reactions, I was able to dispense with the need to actually perform tests. I also had conversations, the ability to do this took some time to develop.
What’s required for these techniques is both a belief that it’s possible, and a belief that it’s useful. After a few years of communicating with my subconscious this way, I slowly stopped doing it. My mind and I are largely on the same page now, no need to do any big talking. Every few months or so I’ll do a test or two, just to remind myself.