There are several types of dreams. Nightmares, calming and soothing dreams, dreams about loved ones, and dreams about strangers. My favourite dreams are day dreams that happen when you are awake and conscious of your thoughts. You can guide your thoughts in a different direction and get creative ideas.
Some people only dream in black and white. I am a lucky dreamer who dreams in colour but since I am a designer, I prefer to say CMYK.