You write down a paragraph or two describing several different subjects creating a kind of story ingredients-list, I suppose, and then cut the sentences into four or five-word sections; mix em up and reconnect them. You can get some pretty interesting idea combinations like this. You can use them as is or, if you have a craven need to not lose control, bounce off these ideas and write whole new sections.
David BowieThere's a thing that just as you go to sleep, if you keep your elbows elevated that you will never go below the dream stage. And I've used that quite a lot and it keeps me dreaming much longer than if I just relaxed.
David Bowie