Preheat oven to 325 degrees F.
Prepare the ham by placing it in a roasting pan flat side down. If using a glaze, score the ham with shallow cuts to allow the glaze to penetrate the meat. Brush the glaze over the ham.
Add ½ - 1 cup of orange juice to the bottom of the pan.
Cover the roasting pan with foil.
Heat for 10-15 minutes per pound, or until the internal temperature of the ham reaches 140 degrees F measured with a meat thermometer.
If using a glaze, baste the ham every 20-30 minutes with the glaze.
Allow the ham to rest for 15 minutes before serving.