There isn't so much a 'correct' way for the language. It's more personal preference or what the standard is for your team. I usually use the myFunction() when I'm doing my own code. Also, a style you didn't mention that you will often see in C++ is my_function() - no caps, underscores instead of spaces.
Really it is just dictated by the code your working in. Or, if it's your own project, your own personal preference then.
