In Chapter 20 of The Catcher in the Rye:
... I kept worrying that I was getting pneumonia, with all those hunks of ice in my hair, and that I was going to die. ... Then I thought about the whole bunch of them sticking me in a goddam cemetery and all, with my name on this tombstone and all. Surrounded by dead guys. Boy, when you're dead, they really fix you up. I hope to hell when I do die somebody has sense enough to just dump me in the river or something. Anything except sticking me in a goddam cemetery. People coming and putting a bunch of flowers on your stomach on Sunday, and all that crap. Who wants flowers when you're dead? Nobody.
What does Holden mean by "fix you up"? And, who is he talking about when he says "they?