I don’t generally use any fixed method for coming up with new ideas, although there is a method called TRIZ which is pretty good for this. I spend a lot of time thinking about things in strange places, like waiting for a bus or in the supermarket. Sometimes things just click into place, or something triggers a thought that is the answer to what you have been struggling with. It can be a case of the answer coming to you once you actually stop thinking about the problem.
Comments