This technique or strategy works on the idea that our short term memory can only hold an average of 7 things. We can therefore decrease the amount of things by increasing their size.
An example of this would be breaking a phone number up into two parts and remembering a string of 4 numbers instead of 8 different numbers.
In order to store what you have learned effectively, it is important to make meaning of the information. That is, you must recognise the connections between new information and what you already know and store information with a clue.
To do this will require you to revise notes as you progress through the semester and revisit information frequently.