Been eating cheese steaks all my life and worked in a sub shop for many years so here's how we did it...
Crazy thin sliced rib eye and plenty of it. Nothing worse then a skimpy cheese steak.
Get your griddle nice and hot
Add a little Olive oil and toss on some diced onions and get them cooking.
About half way done, add some mushrooms if you like. I do.
Put the meat over the onions and mushrooms and get 2 spatulas and chop/tear the meat and while it cooks. The meat should never be left whole.
Once the meat is done, line it up the length of your roll and layer on your cheese. I prefer Provolone. American in a pinch. NEVER Whiz. I have never seen anyone eat Whiz on a cheese steak. Ever.
Once the cheese is down, lay your roll on top and give it a few seconds to let the cheese melt.
Put one hand on the roll, and get your spatula in the other under the meat and do a quick turn of the meat and roll together.
Where I worked we made huge 14 inch long sandwiches. I got burned more then once with molten hot cheese sticking to my arm as I did the flip.
As for rolls, I like a softer roll, not a crispy outside roll. Amarosa's are good, but Buono's is the best. http://www.buonobrosbakery.com/