1. Analyze user requirement documents and other documents like software specifications, design document etc.
2. Write master test plan which describe the scope, objective, strategy, risk/contingencies, resources
3. Write system test plan and detailed test cases
4. Execute test cases manually and compare actual results against expected results.
5. Identify mismatches, report defect to the development team using defect reporting tool.
6. Track defect, perform regression test to verify that defect is fixed and did not disturb other parts of the application.
7. Once all the defects are closed and application is stabilized, automate the test scripts for regression and performance testing.