Just keep your eyes and ears open. The set of all possible startup ideas is an infinite one, so no matter what your age/position/domain is, you can, at any point in your life find one or more ideas that can be turned into a startup. How to find them? => Just be a keen observer for a couple of days. Look at the people around you and assess the stuff that you go through on a daily basis and ask yourself whether you can fix something that's broken or do something to make it easier. The next question is, how better will your target customers' lives be when you solve that problem. If the answer is "a lot", then eureka! you have it. It's perfectly okay if the initial user base that you have considered is very small. But your solution has to make them love you very much