Bring your own linens, blankets or sleeping bag and get a good mattress topper you can easily bring with you. Also get some antibacterial fabric spray for the bed and wipe down everything in your bunkroom so you don't get other peeps germs.
The mattress' at my station aren't that bad. I bring my own sheets (XL twin cheap-o Walmart set) a blanket as a comforter and my own pillow. If the mattress' sucked at work then I'd buy a nice foam mattress topper.
I also keep a heated blanket at the station for those times where the station feels like the South Pole.