When your mat is first unpacked, it may have a tendency to curl or try to return itself into the rolled-up position. To help your mat flatten out quickly, simply place the mat on the floor or another flat surface and keep it at room-temperature. Place a few light weights?such as liter bottles of shampoo or gallons of water) on the mat’s edges. After 12-24 hours, the majority of the curling will be gone; however depending on ambient temperature and humidity, it may take a week or slightly longer for the mat to lie completely flat. Avoid using the mat until it lies flat on its own.