If you can, start selling to real customers to test the market. How you do this will depend on the type of industry you are in. You may want to mock-up examples or prototypes, offer your work for free to get a foot in the door, produce limited runs of your product or launch your business part time while you’re still working. Balance market validation techniques with the cost, so you’re feel confident to keep going if the feedback is positive. If the cost to develop a prototype or production run is low, consider making a start and see what happens to demand and if it succeeds, then scale up. If the cost to do this is high then before you commit your capital, conduct more customer research and testing to ensure your idea is feasible.
Anything to track what customers will actually do is like gold and will give you a better estimate of demand.
After these 4 steps you’ll have valuable market and industry information to give you a much better understanding if your new business idea is viable. Use this collection of insights, research, data, feedback and conversations to guide your decision to launch.