This may already have been mentioned, but I know that the vet has always told us to try to keep the cat from jumping when he/she first comes home so as not to disturb the stitches. I have to admit with all the cats we have had, this is nearly impossible: if you are a cat person, you know they "march to their own drummer," and to heck with what you want.
I have found it easier to keep other animals and kids away from "the invalid" if possible. I also discovered that if I sit on the floor to read or to watch TV, the cat will generally want to be with me.
I would then watch behavior, eating and drinking, use of the box, and the attention the cat shows to the stitches. My cats never had to wear "head gear," but it may depend on the vet and the specific circumstances of the cat's surgery. Either way, it doesn't last long; I figure the cats know more than we do about how they are feeling, and as I said, they are tough to control.