There are several ways to make fake Intestines. One of our favorites is by making “Guts” using spray foam insulation. We recommend spraying the foam onto plastic garbage bags (outside). Remember that the foam will expand considerably as it dries, so be sure not to make your intestines too Thick!
Once it dries, add veins using a blue marker on the foam “intestines”, then spraypaint them tan & red. Depending on whether you want them bloody or au naturale.
To give the illusion that someones guts are hanging out, take a pair of pants, stuff them with “guts” so they are hanging out and it will appear as though their insides have been spilled.