Take clear notes that you may understand
If you're going to be reviewing your notes as a study guide, make sure you're able to read and understand them. Without being to read your own handwriting or what you meant to say things will be challenging. Instead, make sure you add all of the useful information you may need to use in the future.
Clear out other activities and focus!
Once you've collected all of your useful information, make sure you won't get distracted. Try to study in a quiet area, for example, your room, a park