google it, park has a great video tut
basically, you wanna move the small "pieces" laterally (imagine milking a cat)
then move them up and down (imagine moving a volume lever up and down on a dj turn table)
if its still stiff, take the chain tool and twist it 1/8 of a turn, if it stiffens more, twist it from the other direction 1/4 turn (to compensate for the 1/8 turn you did earlier)

hope my weird descriptions helped