If you're using the seating/crimp, die, then just do like the instructions say. Set the seating depth first, then screw the entire die in a quarter turn or so, for a firm crimp. (Remember to turn out the seating knob the same amount)
If you use the Factory Crimp Die, which I highly recommend, you seat in one stage, and crimp/post size with the Factory Crimp Die. The Factory Crimp die does use a knob to control the amount of crimp.
If you're going to load handgun ammo on a single stage press, the Lee Speed Die is really nice. One die body does everything.
[This message has been edited by WalterGAII (edited November 20, 1999).]