If you were to ask the Google machine you may get a few links or a basic description. My experience with mysticism is it's taking an awe into the wonder of it all with a sense of a deep understanding as to what it means. This is usually a different answer for everyone because we all have different life perspectives.  Being a mystic is to simply just be and to not wish to move too fast because you're experiencing realities on different layers at the same time. For me I like to meditate to reach a higher or lower vibration depending on what I'm working towards/through. I find it's the ability to go within ones self and explore the connections to source, God/ Creator, spirit and other dimensionals.