★★★★★
Cut the corner off of an old pillow case so it is just the size of the cat's neck. (Reinforce the neck with some quick stitches so the cat can't rip the pillowcase open if he gets a paw out. )
Make a drawstring for the bottom of the pillow case that can be drawn closed quickly.
Sneak up on the cat when he is sleeping.
Despite my monster cat hating this procedure (I'm 70 years old) he seems to understand that I am trying to help him doesn't seem to hold any grudge.