Before you think about doing any niche research, you need to ask yourself a few questions. it's not necessarily about finding your passion – only because not all passions translate into a marketable niche. You do, however, have to enough motivation to sustain whatever niche you choose.
When first starting out it is a good idea to find a topic you know something about. Once you learn the roles in a few niches you can think about moving into topics that are foreign to you, but may have strong profit potential.