baby play mat waterproof
https://post-wiki.win/index.php?title=10_Principles_Of_Psychology_You_Can_Use_To_Improve_Your_Baby_Playpen_Mat_50x50
Take a look at your mat periodically for indications to wear like threads being loose or damaged foam. Fix and replace if need be. Always store it in a dry area to reduce the possibility of mold growth.