The Shadow was a radio show started back in August of 1930. The Tag line for the show was What evil lurks in the heart of man only the Shadow knows. There was also a movie that cam out in 1984 with that title based on the radio show.
Tha Shadow I am referring to however , is that of CG Jung it is a tern he used to describe your darker side that which you repress or your subconscious.. For I want to talk about Shadow work. Or unlocking your unconscious mind.
First off I want to state that to do this kind of self work it is important to let go of judgement about all thing but mostly about your shadow self. This work should be done with unconditional love for your self. A state where you have connected your he4ad and your heart, this is possible because your heart has neurons too.
You can look at this a an archeological dig, I recommend your current life first. Unless you find what is triggering you goes back further than that. You will need a journal and or a sketch pad which ever way you like to express your self. You could start with those things that trigger you. To start the dig you start a meditation connecting mind and heart , then focus on the trigger or trauma that you want to resolve. Meditate on a key phrase for about ten to fifteen minutes. Then write down your observations, thoughts or hunches. You can also sketch them out or paint etcetera.
I will point out that shadow work can reveal hidden talents or attributers so it is not all about your dark stuff. There are treasures to be found too. These could be things your suppressed because you feel they make you vulnerable. or thought wired. It really could be anything like intuition, clear hearing clear sight. thing you were berated or felt judged for.
I would also like to point out this time is the best time to do such work. This time being when the moon is waning basically a couple of days after the full moon up until the new moon. I would recommend that you write down those dark things which are not gifts talents on a piece of paper and then toss the list of thing you want to release and then burn them with a chant : I release this pain/ trauma and fill myself with love , repeat three times and then let it go. It would be good to follow up with some uplifting music or whatever make you feel happy. 