Regarding what it feels like to move from 3rd Density to 4th Density. This will be scarcely perceptible. There is no pain. There is no sensation. The impact is not from the entity's physical body, which moves as a whole to the other density, but from the surroundings. Bear in mind that we, the Zetas, move ourselves between densities often in our work. We also move humans between densities frequently, during our endeavors. Humans sometimes recall these instances, and state with amazement that they moved through walls or the like. They are adjusting to their surroundings. The move between densities is graduated, so that a move is not necessarily complete. If physical barriers are to be overcome, we, the Zetas, can alter our or human densities slightly, so that communal passage between what would be considered solid objects is possible.
Let us state simply that in changing to 4th Density, as the Earth will, shortly, humans will not be aware that anything has happened. Spiritually the humans may feel more aware of other's feelings, as though spirituality increased in all those around one. This will not be understood to be a density change in most humans, who will ascribe the change to other influences.