[tren]

I agree with this. I generally spend a bit of time creating a single card, with the front being a question that I come up with myself based on the concept I want to understand.

For example, when I was learning about DIY Bio, one of my cards might look like:

Front: "What allows plants and algae to photosynthesise sunlight, carbon dioxide and water into energy?"

Back: "chloroplasts"

My memory isn't great and I think rewording what you've read helps in the process.