Best advice for a software tester: make mistakes.
When it comes to black box testing (testing software from user’s perspective), let all your imperfections loose! You don’t need to be a professional user all the time, you can be a clumsy user misclicking something. This kind-of-out-of-the-box-testing-strategy hits security parts. And, trust me, those are the most interesting bugs which can even break the system.
Most of the best bugs I found were found by accident. I did something that I was not intended to do, and, bang – beautiful bug appears. Of course, usually bugs like that are really difficult to reproduce because being such a free spirit and doing something unplanned, you cannot remember exactly what you did.
Trying to reproduce that bug is a long journey sometimes. However, it is wonderful. Your adrenaline is rushing to catch the leg of that bug again. You are a little bit bitter that you slipped it and cannot remember how to reproduce it. And, you just cannot give up because you had it in your hands, and, it’s one of the best bugs you found. The ‘destination’ of finally finding that accidental bug is more than words can describe. It fills you up with harmony and self pride.
Accidental bugs are the best in my opinion. They are the ones that define the purpose of manual testing:
Humans do mistakes and that’s why automated testing will never substitute manual testing done by imperfect humans.
Set yourself free! Get crazy with your software. Misclick, choose another option, experiment, and… break it.