What are the best approaches to write a test class in salesforce?

Best Practices to write test Class :-
-Do not put (seeAllData = true) in test class otherwise, use it for exceptional cases.
-Use @isTest at the Top for all the test classes.
-Test in bulk
-System.runAs() method to test the functionality in user Context
-Use Test.startTest() and Test.stopTest() statement to increase Governor Limits