Noted. The price of a ribeye steak made me raise an eyebrow and perhaps not use it for first experiment tho. Will check what alternatives are at the store [currently just browsing big-chain apps]
It's a simple thing really.
1 - Buy adequate steak..ribeye is traditional. Slice thin or shave (if you have the means).
2 - Buy good long rolls. They should not be crunchy at all but can have a little bit of firmness to them.
3 - Buy good quality cheese. Not sure what you can get there. If you can get Cooper Sharp American that is the best to me but Provolone is also excellent. Swiss works. Cheddar is for burgers. No french cheeses.
4 - Onions, either fried or caramelized, are a good topping choice. Philadelphians do not put Bell Peppers on there but you'll see impostors like Subway offer that. Hot or Sweet Cherry Peppers are acceptable.
Cook the shaved ribeye to near completion, then put your cheese on top of the shaved ribeye while it's still on the cooking surface you're using so it can melt while the steak finishes. Then turn your roll upside down and put it on top of the pile of cheese and steak. Swallow up the ingredients with the roll, flip it over, and then roll it up right with aluminum foil to get it all shaped properly. Unroll and top with peppers and/or whatever sauce you prefer. A lot of Philadelphians use ketchup, some use mayo, and the true weirdos use both. I like mine with caramelized or grilled onions and then instead of adding cherry peppers at the end, I hit it with some Sriracha sauce.