Process to create test scripts...

• Get a thorough understanding of the application under test -- either through documentation, or from BA/ product owner or the team. 
• After an understanding of the application and the requirements, identify the scenarios/ risk areas which then give an idea of what to test. 
• Once the scenarios are clear, decide on the test cases and test data.
• Write the test scripts
• Get these reviewed
• Executive the test scripts, report bugs.
• Work with Dev team to close the bugs.
• Report on the bugs and closure.