Door Pannel Carpet

[tcnufed]

I was just wondering how to take the carpet off of the door pannels and replace it with something different.  I have seen pictures of one done with camouflage on here before but I can not find it again.  Do you cut the carpet off or do you have to glue the fabric over the carpet.  I have taken my door pannels off before and I didn't remember seeing any way to take the carpeted section off, but I can't remember.  Thanks for the help.