I would like to know what is good automated manuturing practices
Good Automation Manufacturing practices is also known as GAMP. You can purchase the guidelines from the ISPE. It is a very complete guideline that provide templates on how to write User Requirements (URS), Functional Specs (FRS), IQ/OQ/PQ for automated systems.
see
For more details on GAMP and how to purchase GAMP guides. If you have any specific questions on GAMP I can help.