Talk to 18 of your future customers, ask them about their problems, ignore what they tell you and then ask what they were trying to achieve. Focus on the desired outcome, and the goal it leads to. If you stop hearing new things after 12 you have found solid targeting. Now you have technology on one hand and a worthwhile problem on the other, and you just need to figure out how to apply one to the other.

When staging your plan make sure to put important parts first, so ask your future customers which parts of the outcome they want the most.

So the first part is Listening, then comes Design, then comes the Iterative Loop.