How to become a good C programmer?

[silex]

I would like to become a good C programmer, where to start or not really, where/how to begin getting better? I should probably note that I've been programming on and off since I was 7, for the last 30 years or so. I've read K&R and could program all the examples that are there. I've also read a share of C code and can understand it. It however takes me sometimes to gasp as the design gets more complex and for most part of it is not trivial to me especially compared to Python code. Is there any book to develop the upper level C skills I might use especially the design side?. Is there any reference to the best C libraries or even programs out there? Some half complex, documented C code that could lead me to an eureka or so. Where should I start or more precisely where should I begin the odyssey?