I do this from time to time, especially when I'm pretty tired.

I'd just rest my body, and wait for something to come, images, sound, etc. Though, I don't expect them to come to my actual eyes, but I sort of wait within the spaces of my imagination. I'd eventually come to see pictures, like me doing something. But, until I willfully woke myself up, I didn't realize that those images were passing by. Only after I woke up a few minutes later, did I recall it. To remember my state of mind during this imagery session, I was utterly clueless as to what was going on, and I understood just why it was hard for me to be conscious in a full fledged dream. Showed me how much I needed to work on! The dream world truly is a large abyss to the new explorer!