How would you be able to follow construction schedule on the right pattern based on the Pert CPM?

The critical path method is a very simple and straightforward means of managing activities that has the potential of causing you to miss your deadline.
Ideally the tasks along the critical must be monitored very closely and updated as soon as a change is implemented.
This method of managing construction projects allows you to have a clear view of all the activities that will be affected if a change occur and allows you to provide valuable information (regarding budget, timeline and the overall change in scope) to guide the change process.