How To Kill A Character

I don't know.

Simple as that. I've not a clue how to kill a character and make you, the reader, feel any sympathy. 

While we're on that score, what if sympathy isn't what I'm after? Suppose I wish you to cheer at the death of my antagonist? Or perhaps my protagonist? What happens if you despise my narrator, and s/he dies? 

I do not know.

You see, in my current novel, nobody dies. Nobody needs to. The story centers on what it means to live the life you have already, to live it more fully even; while jousting with death seems an insatiable temptation, I discovered rather quickly this set of characters do not, in any capacity, understand death. Indeed, the only two characters who do--one lives his life without abandon while the other enjoys her bubble-wrapped existence. Yet both suffer from an intangible, indescribable emptiness which they seek to fill in completely separate ways.

But...

My next novel, which takes place in the afterlife, centers on death. Duh, right? Truthfully, I'm a little worried how things might turn out because it's been a few years since I killed a character and never successfully. That's okay, though.

I'm a writer. I can handle this.