Heat Meatballs in Microwave as directed on package.
Heat Sauce either stove top until bubbly or heat in Microwave covered with plastic wrap until hot (careful removing it, bowl will be hot)
Some may want to add Mayo to the bread if you like mayo.
Place Meatballs onto roll (as many as you'd like or will fit)
Place your cheese slices on top of meatballs
(If you'd like you may want to place your sandwiches onto a cookie sheet and place them in the oven on broil for like 4-5 minutes to melt the cheese and heat up your sandwich. Watch carefully as not to burn them.
Some may also want to add Salt and Pepper or Italian Seasoning to "spice it up"a bit.