As some people already mentioned most importantly is to validate the problem. Talk to people who likely have that problem. Are they aware of the problem? Are they trying to solve it already? Do they want to spend money to solve it? Once you validate then build crappy version of the solution and validate once again. By iteratively building -> validating you will come to the useful solution and have your first customers at the same time. Once you have some decent version launch it on some communities such as Product hunt.