First, I would like to clarify what 'spiritual moments,' to me, are.
When I was little, I used to think epiphanies are very tangible experiences, such as hearing a burning bush talk, or being enveloped by blinding light while a choir of angels sing. 
Of course, I thought that how films and books portray them was literal. Only as I moved on to young adulthood that I start to see them more of inner, and symbolic experiences not necessarily involving religious entities.
So, spiritual moments for me, are moments of clarity. When the mind is at complete peace, because it has been silenced by something higher than thoughts.
As thinking beings, it's hard to pacify our thoughts. We question every little thing, what it means, why such exists. We try to rationalize even the most mysterious of things, because we need to grasp it somehow. It's our instinct. Like a child with so much yearning to understand how the world works. But then, there's only so far our logic can take us. There's a point when our minds just get baffled by the impossibility of what we're trying to do, and the elusiveness of the truth we're trying to seek.
And that's when these 'moments' usually happen. When our logic finally raises a white flag, something unnameable just 'visits.' And all the answers to our questions are finally answered, not necessarily with words, but with a very particular feeling, or an image that holds special meaning. A wordless whisper, that somehow shakes our beings like a roar of thunder. That renders everything else insignificant. Even the questioning, and the questioner itself.
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So, to answer @Artisan 's questions (sorry for the long intro),
- What you are doing when you experience your spiritual moments?
Before experiencing? Rationalizing myself to death. Or sometimes just letting all the emotions flood. Then suddenly just dropping them, out of exhaustion, usually not deliberately. More like, that 'letting go' moment when you're hanging off a cliff with all your will, but just really can't hold on any longer.
- Where/When do you experience your spiritual moments?
During times of 'walking in the valley of the shadow of death.' (Wait, I just said 'cliff,' then suddenly I'm in a valley. Oh, it's after the fall. 
)
- How often do you seek out your spirituality?
Everyday for about seven years now, except for short periods of obsession to particular things that distract me (like this MBTI typology thing, since I just found out about it recently).
- How important are these moments to you?
They're what keeps me alive 
Well this was a spectacular answer and pretty much sums up what I would say as my definition.
I agree they are moments of Clarity. Once my "awakening" began to include non ordinary reality experiences I would say my spiritual moments now include a deepening connection to Source Energy.
What was I doing when I had these moments? Using some kind of tool: a method - a practice - a physical movement - drug - toning - dancing - drumming etc. Once I made connection with my first spirit animal in 2012 a whole new world opened up for me like going to a splendid buffet of mystical experiences.
A life event that caused me a great deal of pain(loss of father and boyfriend all in one week) woke me up to the point where I declared out loud to no one there: "I am tired of this crap! For once and all I am either going to find a way to love myself so I don't have to rely on any other person to make me feel good - "or else" - I'll complete suicide". The Universe heard me and I went on a Quest to learn how to love myself.
My first experience was in an experiential seminar with Linda Star Wolf - a Shaman. There was a group of about 20 of us seated or lying on the floor while she and a couple of assistants beat drums and played music. Ahhh...the music. I remember this now and smile. The music she played was all instrumental and held themes to evoke feelings and images within the human body mind. It was if I was transported to different places and times.
I use music a lot to create my sacred space and meditations.
Anyway - it was during this event guided by the Shaman and her assistants that I had my first vision journeys. I had two: one was of being enveloped in the feeling of unconditional love and hands gently reaching down to touch me on my head and my shoulders and pats on the back. It was the most amazing thing I had ever experienced and I cried and sobbed in a curious mixture of joy and grief as my connection with source energy was made.
Or...truly something was removed and my connection point was no longer blocked. Once this happened in an instant I now knew why for all those years whenever I had thought about something larger and outside of me I would get this contraction in my stomach and I would feel sad.
The other vision was of Panther forming in my vision and asking me if it was okay if he came "into" me. I checked to see if I had any fears and there weren't any...so I said yes. Hahahaha...I still laugh whenever I think about this moment. Panther - he was a black jaguar - put his forehead down to mine and touched it...sort of in acknowledgement of our agreement that he do this....and then moved towards my chest and I watched in amazement as a panther slowly walked his way into my body. I even saw the tail move a bit in the fashion of cats as it slowly disappeared within. I remember I laughed....not only with delight...but also at the absurdity of what had just happened.
The next kind of similar experience was later in 2012 I attended a 2.5 day training seminar with another Shaman named Sandra Ingerman. There was about 200 people in this one and we lay around or sat in a huge hall up in the Rocky Mountains. Just so you know...I have read higher elevations with lower amounts of O2....lead one to have more visions.
Sandra Ingerman is a wonderful lady full of the wisdom of the Earth. She used her drumming and power to lead us all on Journeys. It was there Bear and SunConure became my spirit guides. She taught us many ways and practices of the Shaman and we had amazing journeys including finding long lost spirit guides for each other.
Methods and Groups of People with Intention
On a side note: Back in 2007 many things happened to me but an important one was the fact I began doing Vipassana Meditation and met with a group once a week to facilitate this practice.
My Quest continued to have more and more amazing experiences of non ordinary reality and I gained more and more clarity.
You asked How often did I seek these experiences? I approached it like meditation practice. The more I sat with myself the more of the experiences I had. Mostly they came randomly until I learned how to see myself trying to control the outcome of my experiences. The more I noticed that ...the more I let go of outcomes. Then I had more visions and experiences. So in a strange way I was seeking it during my meditations but then learned not to seek them...and then I started having them all the time.
I've been doing this now for 3.5 years and I live my spirituality all the time now.
And Yes... it is what's keeping me alive and here...literally.
