Things crop up. Random things. The raw materials of dreams. For me it's mostly in black and white- high contrast, glittery black and white, but with sudden- gone before you can focus- flashes of brightly coloured scenes- a field of grass, children leaping into water, a man bending over a rock pool- One time I was going down a sort of tunnel made up of a collage of faces- real faces, not generic ones- as if cut out of old photographs and pasted on the wall. Another time the thing I was seeing- which seemed to be some kind of rolling wave- not necessarily made of water- was overlaid with a fine rectangular mesh as if for the guidance of any artist who might have wanted to draw it. I hear voices too. Rarely saying anything of consequence, but startlingly real- as if the speaker were standing close behind me.
There's a word for all this sort of thing- hypnagogic. I'm told that if you hang around on this level long enough- with properly focused intent- you can take your consciousness out of your body and off into other dimensions.