Normalization should be part of design process. Make sure that proposed entities meet required normal form before table structures are created. Many real-world databases have been improperly designed or burdened with anomalies if improperly modified during the course of time. You may be asked to redesign and modify existing databases. This could be a really big endeavor if the tables are not properly normalized.
Use an Entity Relation Diagram (ERD) to provide a big picture. The ERD shows a macro view of an organization’s data requirements and operations. The ER Diagram is created through an iterative process which involves identifying relevant entities, their attributes and their relationships.
Normalization procedure focuses on characteristics of specific entities and it represents the micro view of entities within ERD.
It is difficult to separate normalization process from ER modeling process. The two techniques should be used concurrently.