Go out on a day with beautiful distinct clouds and start watching them. Treat these clouds as Rorschach patterns. Describe them aloud. Describe the changing patterns. Perhaps you can wish the pattern to change to your desires.
Some people play at cloud melting.
On a day with a few clouds they stare at the clouds and try by will power to make a part of the cloud to disappear. Whether this works in reality or not is not that important. As far as your creativity is concerned it is important that you give yourself no boundaries and are ready to try far out but harmless ideas. I personally do not believe it is possible to control the weather through one's will power or desires. However, the few times that I have tried to make rain, coincidentally it has rained.