First of all, understand recommended reading which is given in the starting of the concept.
Understand properly what is the topic about. If you don't understand the topic then read about that topic from basic.
Now, start reading the topic. Also, start making notes of every topic if you think its important.
After completed reading little information, try to remember what you have read.
Try to connect the topic in examples with something that you remember easily like connect with some past experience.