Pattern the birds early prior to the season but never call them. Figure where they go mid to late morning and then again in the afternoon. Use a decoy(s) and call very little in one of the spots they frequent. On pressured birds I very seldom use more than a short cluck or a very lite yelp and stay set for a long time. Don't expect the thundering gobbles after the first week as they get call shy and quiet down , but they are still around. Most of the other hunters over call and leave early so be patient, stay later and let them come to you.