Inside I usually use a pizza pan, and never have an issue with sticking. It has perforations n it , so cornmeal or semolina would be a disaster, the directions just say grease the pan ( which I do). I do rotate the pizza half way through to make sure I get even cooking. Also, at this time, i check for bubbles, if there is a huge one Ill pop it. The dough says cook at 450, I cook at 425, it just works for me. Ive never tried at 500.
Outside, on the grill, I use the stone,peel, corn meal technique. The grill gets some good heat. My grill is big enough to have the stone one side, and free grill on the other. I start the pizza off on the stone, close the lid, and let the magic happen. Once the dough is done and cheese has melted , I slide the pizza over to the grill side for that last minute scorch on the bottom to get that ' grill' flavor.
Thats what works for me.
Ive done directly on the grill before, it worked fine, but I prefer the stone/ grill method better.