The first step is the "target result". Check the differences between the goals we set at the beginning and the goals we have achieved now.

The second step is "process reproduction". Looking back at how the process came about, it can be roughly divided into several stages, and what happened at each stage;

The third step is "gain and loss analysis". Analyze what we have done well, what we have not done well and why.

The fourth step is "summing up experience". From summarizing what we will do if we do the same thing again to summarizing the laws, principles and methodologies that will guide our future work.