There are two options.
1) Use your regular pizza dough, roll it out into a flat disk about 8" in diameter (adjust the diameter to give you the size calzone you want). Brush the edges lightly with water, add filling of ricotta cheese, mozzarella cheese or your favorite cheese blend, add desired vegetable/fruit filling along with pre-cooked meat if desired. Fold in half taking care to line up the edges, tightly crimp the edges together, transfer to a baking sheet, using a sharp knife or scissors cut a few steam vents into the top, brush with egg wash or cream/whole milk/melted butter and sprinkle with shredded parmesan cheese, bake at 450F until golden brown, brush or spray with garlic butter to which you have added a small amount of dried basil/oregano, set aside to cool for a minute or so before serving. This is one of our all time favorites.
2) Make a "special" calzone dough. Starting with your regular pizza dough formula, add unsalted butter or Butter Flavored Crisco to bring the total fat content up to 5%, add 5% whole egg (be sure to reduce the water content by 75% of the weight of whole egg added). Prepare the dough by your normal manner and follow the steps above for forming, filling, sealing and baking the calzones. This second method makes a richer, more pastry like dough.
Tom Lehmann/The Dough Doctor