"There is a general rule when learning CCIE, that is, the more you know, the faster you forget. There are two ways to effectively remember the CCIE training knowledge points you have learned for a long time.
Method one, intensive reading
There are many ways to intensively read. The common question-and-answer method of intensive reading is to write down some small questions while reading, and then answer them with simple answers. When you read the first time, you may feel that there is no problem, then read it again. Answering the answers to the questions is simple and easy to remember. Don't confuse multiple concepts in a small problem. When CCIE training asks questions about configuration, remember to write down the main code. If you are organizing electronic documents, don't copy and paste the code. At the same time, you should write down some good pictures, which will help you remember. When you read it a few times, the number of questions may be less and less."