Steven Johnson in this TED Talk talks about the emergence of ideas and the three things that he emphasizes are:
You need to have a informal environment for the ideas to come. Not many ideas have been generated in the labs.
Ideas take a lot of time to develop in your sub-concious, though they may appear to you in a Eureka moment. Incidentally we get to hear only about the Eureka moment and not the thought process that may have floated in the mind for years before becoming that idea leading to Eureka moment. But it is important to understand that Eureka moments do not happen out of air.
Your ideas need to connect with other ideas. Ideas come by interacting with other ideas. In fact he says Idea is a network in itself.
I agree with all of this. And would like to add, have an open mind…keep your conditionings in check and you would find many more ideas coming your way. Like Steven says ‘Chance favors the connected mind’.