Pymie is awesome for crappie (and in general). Follow Blue Lagoon's tips, and you should be in good shape (on just about any lake in the region). One thing to note, you will snag and lose a lot of tackle, they love being in cover. Many times, refusing baits that aren't right in a sure snag. If so, try to find the sweat spot, that they are biting and not snagging. Don't worry about retreiving every jig/bobber, or you can ruin a productive spot. When you go out, have a good supply of jig heads and bobbers handy. You can always collect your bobbers when you are planning to leave that spot.
Do a search on this site for some of Chauncy's posts. He seems to fish Shenango more than Pymie, but much of his info translates to just about anywhere, in the region at least. There was a nice & informative article featuring him that someone had posted a few years ago.