I used to do that as a child.I would lie down in the grass and then relax ,staring at the puffy clouds passing above my head,trying to make out shapes of animals ,people ,things.
It is great way to let go of all mundane worries.It was rather something for fun to me rather than divination back then.
Sadly where I live now the sky is almost always gray and with too many clouds to attempt to divine.Clouds look as massive gray mass that moves pushed by the currents.
You can divine either using your intuition ,when it comes to what shape you observed into the clouds ,or even you can consult a dream dictionary.
After all dreams are messages from our subconscious and divination work is based on similar concepts.