One of the most underrated study strategies is teaching someone else what you have just learned.
When you explain a concept to another person, or even an object!!, you’re forced to organise your thoughts clearly, use your own words and consequently identify any gaps in understanding. It’s one thing to agree to understanding the content but being able to explain why or how a topic works is another. If you are able to turn to another person and break it down so that they themselves understand, that’s when you can truly believe that you yourself understand.
Even I use this technique as a tutor with my students. After working through a problem together. I will turn to my student and ask them to teach it back to me. At first, they are sometimes confused but they start to understand how much it helps in consolidating knowledge as they need to dig deep into all topics of the content to explain. Often, if they stumble, I can clearly see what knowledge gap I need to address. I can then provide certain questions which will address this gap and hopefully build their confidence as their learning is reinforced.
This technique can be used even without a tutor or friend. You could look at yourself in the mirror and try to explain it to yourself. You could try explain it to a pet or even a stuffed animal. If you really want to see what level of understanding you are at, you can record yourself explaining and see where you stumbled and quickly address this gap in knowledge by going back through notes or the textbook.
This method is great for changing passive learning to active, really ensuring that students are understanding all aspects of the content.

Lily Powell