I use to use my wife's white nylons to camo my guns when hunting predators in the snow. You just cut one of the legs and strech it over the entire gun. I used the fiber glass tape to bond it to the gun but don't put the tape on your gun. Wrap and place the tape on the nylon. Cut out the actions and magazine feed and it will work. It does not look good. Not how they use to look on her legs. LOL LOL
Also don't put them over your face if you should go in for a cup of coffee at a convience store. You might get shot.
However I have found out from other predator callers to use the Vet white horse bandage tape. You just wrap the entire gun with it. It does not leave a residue and you can use it again if you place it back on the spool. You get it at Tractor Supply or any farm store. When your done you shotgun or rifle will look like a mummy but it feels a lot better then just a nylon on the gun.
however both will work. In a pinch use the white nylon. However go to the farm store and get some of the white tape I referenced above.