Once you've removed the nut make sure there isn't a washer in there. Turn the puller bolt out and then thread the puller body into the flywheel by hand, once it's snug tighten it down with a wrench. Now with the wrench on the puller body, tighten the puller bolt down. You want it tight, but don't go overboard. Sometimes they'll pop right off, sometimes you have to give the puller a few taps (taps, don't go wailing on it) with a hammer. A non marring brass hammer would be ideal, but any small hammer will work as long as you keep it square.