Personally, I think there's a fair bit of reason to believe that both Zen training and hospice experience are useful to facing one's own death. Cultivating awareness of impermanence is central to Buddhist thought. Zen includes such traditions as composing one's own death poem  and specific meditations on death .
I also found spending time in a hospice to be useful. Anything unknown is hard to think about and possibly scary. Being in the presence of death made it more real for me. And I'm not alone in this; a hospice program founder has an excellent talk  and book  on what people can learn from hospice.
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