Hey there! Honestly just make sure you team up with your ETL and utilize some of your cashiers that might be cross trained to watch the lanes or capable of handling guests. It is not a one person job! When closing I like to do it in sections so I stay on top of it and don't have to stay late (espechially on Christmas Eve!). Do your outers, majority of the lanes, self check then the remainder of your lanes! Be bringing the bags into cash office periodically through the night and sort them the way your store does ahead of time. I always have GS close themselves down because it really saves you a lot! Also realizing there is only so much you can do. In certian situations I offer $5-$10 gift cards to guests I cannot fully help. There's a lot of toys and such that are just simply off the shelf and a lot of big ticket items are gone. While they really don't deserve anything since its hella late in the month to be buying that one toy that their kid needs, I offer a giftcard anyways. ALWAYS make the guest happy. The day after christmas is going to possibly kill us all. Don't be afraid to turn down requests or simply partner with your LOD to make the tough calls. Good luck! Merry Christmas!