This is how I look at it. Take a fairway wood or driver and lay it out across your back foot, pointing down the target line. Sort of like this

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Now either using your shoulders or your hands (whatever you feel comfortable with) take the club away and when it is parallel to the ground the shaft should be over the club shaft on the ground. Not way inside it or outside out. From that point exactly the wrists should start to set (because if youve kept your lower body still i.e. not swayed or slid you should now be at the maximum point of extension) and the club will come up, inside and across your shoulder as you continue to turn. If the club doesnt start to come up and inside at this point I know Ive shifted to much weight to the right

Luke Donald is a great example

http://www.golfdigest.com/instructio...ld/donald.html

And look at the palm tree behind his trail hip. He doesnt obscure it at any point on the BS which means he isnt swaying and thus maintaining the radius between his arms and chest which allow his wrists to hinge naturally at the correct point (when the arms are at maximum extension)