I want to start a new business but I don't know what business to start. I know I have certain talents and aptitudes, but how do you find a gap in the market? I want to go where the money flow is and also where my aptitudes and skill sets could answer that gap to start a successful business.
I love this question. The fact you've asked it makes me think you have a great chance!
You absolutely can go after gaps in the market. Here's my suggestion for a methodology.
Start with some questions.
First, what do you know about? Your particular knowledge, skills and experience will shape how you attack a new challenge. Be thorough in looking at what you know about and think through how you acquired that knowledge - which will tell you something about how you'll be able to build on that base if you choose some unfamiliar context.
Second, what do you care about? It's important to be motivated by more than the expected success. What problems exist in these domains? These may be opportunities.
Third, what means of access do you have to people, products, resources in these domains?
Fourth, what actual resources do you have or could you access?
So having gone through all that, you have (believe it or not) the beginnings of an entrepreneurial toolkit.
'A gap in the market' is really just a way of describing a situation where a problem in a given domain is solved badly for some or all of those affected by that problem. And for an entrepreneur, innovation in such a situation is a question of doing as little as possible to create a better solution - typically by taking some established technology and applying it in a novel context.
90% of the time, you're going to come up with a new approach (change the technology, the route to market, the packaging, the pricing etc) that would create better solutions... but no viable means of bringing it about. (Not viable includes for instance that there's not enough 'money flow' - using your term - to make the innovation attractive.) But even with those, you're adding to your knowledge as you go.
And sometimes you'll find yourself looking at something you could actually do. And those, you need to research further - especially among the people who could be your customers - to make sure the problem you've identified is real, that the existing solutions do fall short, and that your approach would be attractive.
And for what survives this filter, start thinking of your minimum viable proposition - an affordable (for you) test to validate your idea and start building it out. You'll find lots on software minimum viable products - and while these ideas are easiest to work out fully in web services, live market trials are possible in all kinds of off-line contexts - because the web world has also given you access to people, talent and all kinds of physical goods in amazing ways.
You don't really need a "gap" just a underserved niche or niche where you can do better then others.
My route was to actually enter the market where I could see a healthy demand and produce a similar product to something already out there to make enough money to run. After a while, talking to customers, I worked out what the next emerging trend was in that market and focused entirely on it. Finding the gap without being actively involved in the industry on a day to day basis would be extremely hard.
There is no magical short answer to that question, or else everyone would be a successful entrepreneur where the money "flows". The Mark Zuckerbergs of the world just happen; there is little foresight and business planning involved.
The secret sauce is to put yourself in a place where you get to hear people complain about things you can apply your skills in. This can be done in many ways:
It's the classic idea that a startup is simply an itch waiting to be scratched.
This will not work for everyone, but graduate school can be a great place to study problems, develop solutions, and look for opportunities to start a business. Here are a list of possible benefits:
Again, it is not for everyone, and there are plenty of examples of successful companies started by folks without a college or even high school education, but graduate school is often the best place to see technologies on the horizon before they become commercial products.