Well I usually use a pillow.
I’m usually rather forward with it. Made them fall down a flight of stairs. Falling off a building onto exposed rebar. Drowning by concrete. Hurled from a vehicle straight into a wood chipper(no seatbelt) Kissed by death, devoured by a pack of feral cats, Entombed with a mummy, Mummified by natural exposure, Having their heart summoned directly from their chest in front of their family. Having their clothes inverted into their insides. Curses aging them into dust and last but not least
having that bitch thrown out an airlock and then blasted by the ship’s primary weapon.
Some characters are just meant to die. Others may not have intentionally been marked for death but the story just goes that direction. If I do like the character they should get a proper send off. Lots of foreshadowing. I’m not that much of a monster to heartlessly not give the character advance notice.
Sometimes you start off liking a character but then they evolve in ways you don’t forsee and then you hate them with a passion that no star could match. These characters are bound for final destination deaths with as much spite as possible with all speed. Authors like it or not can pretty much be naught but spiteful deities.
It depends on the character and the situation. There’s only been a handful of characters i’ve written who did what they set out to do. They knew they weren’t coming back… But they went anyway. Those ones I have the most trouble trying to keep them alive short of divine intervention. It would be rude to ignore that inherent nobility. Even if they have gruesome ends Valhalla awaits.