oR To begin enjoying your new mattress, simply remove the packing. If using scissors, be careful not to cut through to the mattress. and allow 48 hours for expansion. Place mattress on a flat surface in a well-ventilated room (5 After your mattress is fully expanded, you may begin enjoying the benefits of your new mattress. Due to the unique properties of memory foam, dimensions after expansion may vary; this is normal and will not affect the performance of your new mattress.