Active recall means you are actively trying to understand, sympathize, and explain a concept without any help from any notes or any sort of textbook. (time period: 19:21~24:33)
Explaining a concept out loud in complete sentences as if what you’re in a classroom without looking at any notes.
Step 1: Choose your concept
Step 2: Pretend you’re teaching the idea to a new student
Step 3: If you get stuck, go back to the book
Step 4: Simplify and create analogies