ref http://inderpsingh.blogspot.com/2010/03/how-to-find-more-or-better-bugs-12-tips.html
I copied directly
Well, we know that we do not find all the bugs in the application under test (given that the application at hand is not simple). However, we do want to discover and report the most and the best bugs that we can. You need more ideas if you want to find more or better bugs than you do at present. Here are the tips. Go to the video, How to become Software Testing Expert or read on.
Tip 1. Review the application‘s requirements often. You may notice that no or partial test cases exist for certain requirements. You may find bugs when you test for these requirements. Keep abreast with the change requests/ changes to requirements. Be quick and you may find bugs immediately after a requirement change has been first implemented.
Tip 2. It is possible that you have positive test cases only. If so, create negative test cases for each requirement and execute them.
Tip 3. Execute each test case with a variety of interesting test data (generated for example by the boundary-value analysis technique or pair-wise testing technique).
Tip 4. Test the interface of your application with external systems carefully. This is where a number of bugs may exist.
Tip 5. Another place to look for bugs is the application settings (since this is one area that may be rarely tested in fear that the application may stop working correctly or stop working altogether).
Tip 6. Repeat your tests using other supported client configurations (other CPU/RAM/operating systems/screen resolutions/browsers etc.)
Tip 7. Look at the previous bug reports against the same application or similar applications. See if you can test your application using the ideas or information contained in the previous bug reports.
Tip 8. Do not ignore the cosmetic bugs. If they would inconvenience a user, they should be reported and fixed.
Tip 9. Create a list of items that you would like to test if you had the time. When you test your application, you may find yourself taking mental notes of things that you would like to test later. Jot these things in your list. Come back to the application another time and test the things in your list against all areas of the application.
Tip 10. In case you are working as part of a testing/ QA team, do not restrict yourself to the areas that you are supposed to test. You may find bugs in the other areas. This would also have the nice side-effect of increasing your overall knowledge of the application.
Tip 11. Instead of rushing through your tests at top speed, slow down (I know it is difficult). You would give yourself time to think more clearly. You would start to observe things about your application that you did not observe before.
Tip 12. Finally, take pride in the bugs reported by you. Feel free to mention an interesting bug that you found to a team member.
A word of warning. Do not get carried away if you suddenly start finding a lot more/ better bugs. You should still take the time to contemplate each bug, reproduce it, match it to the requirement and carefully create a good bug report.
Enjoy bug-hunting!
POSTED BY INDER P SINGH AT 9:22 PM