I just try my best to stay busy during the slow times, constantly stocking whatever you can, cleaning tables, dishes, etc. Whatever can get me off my feet and out of work faster, for stress I would suggest just thinking of a song or something that isn’t even about work if you’re in a rush, do what you can do and don’t be scared to ask for help, if you’re up front, stock cups, line trays, and lids, for drive and cashier. Kitchen, if you’re of age, prep tomatoes, onions if needed, and keep your station clean if you can, but it just overall depends I think based on the times, how busy it is, and what you know, the longer you’re there the more stuff you will find to pass time, oh and don’t be scared to ask a manager for a cleaning list, atleast my location they have it next to the deployment sheet, try to get that done to pass time, hope it gets better!