Assuming you are referring to the mats/floor liners:
The WeatherTech website offers the following instructions:
To clean your mats, simply rinse with soap and water then towel dry.
For tougher stains, use a mild household cleaner or diluted vinegar solution. Spray on the soiled area and allow it to penetrate for several minutes before wiping away.
If you have any further questions they suggest contacting customer service.