A recent study showed that keeping a dream journal can make you more creative, or at least score as more creative on the Torrance Test of Creative Thinking (TTCT).
The Journal for Creative Behavior came out with a study where participants took the (TTCT). Then, part of the group was directed to keep a dream journal while the rest were asked to maintain a regular journal documenting an event from the previous day. A month later they were given a slightly altered version of the test. Only the dream journal participants increased their "creative strengths" score. The researchers suspect this is because dreams are more abstract and non-linear than remembered events.
Below are some examples of dream journals. Dream journals are meant to be completed as soon as you wake up. You should sketch and write as much as you can remember from your dream. Your notes can be just keywords that stand out or complete sentences. They are supposed to be as descriptive as possible.
This reminded me of the "Morning Pages" in Julia Cameron's The Artist's Way. The Artist's Way is a 12 week exercise to work through creative block. These are designed to work you through your creative hang ups and open yourself up to new ideas.
Often artist's create groups to support each other as they move through these exercises. At the core of this strategy are artist dates and morning pages. The morning pages are meant to be stream of conscious writing created as soon as you wake up. It's designed to clear the cob webs off the brain. It can be sketches, words, to do lists, whatever is clouding your mind...get rid of it on paper.
While the "morning pages" are different than the "dream journal" they do share the timing, being as soon as you wake up, and the nature of the writing should be spontaneous without much planning.
Creative block is so frustrating so collecting strategies to overcome it is super helpful. Next time it happens try writing first thing in the morning to see if it helps!