Creativity is 5% inspiration, and 95% perspiration. The best way to get an inspiration is to start working on a problem, do what you can, come up with ideas, try stuff. Then the brain will be in a position to be "inspired."
its a bright swelling in your chest with an overwhelming sense of confidence and brilliance. there's a glow all over you and your powerful idea seems to move you, not muscles. it feels similar to pure happiness with a side of awe and a sprinkle of pride. :-)