how?

Creativity - how to get to the core - to let go and really create what is your heart and mind? It must begin with a thought - then for me, maybe a sketchy sketch, then some more thoughts and finally on the computer (which is my paint brush now) and see what happens. But for me it is also very "stream of consciousness" - like running random patterns. ... What drives it? What pushes it along? How come some ideas get done and so many never do?