As an employee you wear either Khakis, or other type of pants (not jeans) that are at least long enough to cover your upper thigh. You also wear an apron and a visor/cut out hat that is to keep your hair out of the way and keep the food clean. No open-toed shoes. They give you a special Subway shirt to wear..and the company changes the style ever once in a while. Depending on the manager/co workers, you can work without an apron and sometimes wear jeans.
A typical life as an employee? Clock in, clean and prepare food if there are no customers, put on gloves and pull out a peice of "sub paper" and ask them what they would like. You say
what type of bread?
footlong or 6"?
what type of sub is this going to be?
what kind of cheese would you like?
is this going to be toasted?
Then there's usually someone else who puts veggies on (or yourself if it's not busy).
You do dishes, break down boxes, wipe tables, fetch more food, cook bread, bake cookies, and give yourself a 6" if you're hungry when things are going slow.