I think it is always dependent on the sphere and level of interest in this matter, that matters. For someone who likes to deal with the physical parts of a system would do better in hardware, and the one who is curious in making things work through an analytical process, is more likely to shine in software. Networking needs the best from both worlds with a demand for an extra Calibre which we know as a knack for communication.
Today there are many aptitude tests and quizzes available online. You can ask the same question to Google which would provide you with the relevant tests. They are indeed a good way to discover your own talent and are fun too. Hope that helps.
As Anwesha rightly made the observation, you need to identify your talent. Having done that you can then proceed to work with it.
Live....and Let Live!