Look closer at those messy scribbles, they show you were really paying attention. A guess means you're actually thinking about what you see, not just snapping a picture. Sometimes the old way of watching was better because it made you work for it.
People are really overthinking cloud diaries. Samf95's example shows it's mostly just messy notes about the sky, not some deep record. It's clouds, not a science project. Hard to see why anyone would get worked up about it.