First of all, you'll need a Totem of Undying, which you can get from killing an Evoker. Once you have one, make sure to either hold it in your main hand or your off hand.
When you come into contact with something that deals enough damage to kill you (falling from a large height, an explosion from a Creeper with no armor on), the Totem of Undying will fly out and give you various status effects, including Regeneration and Absorption. When this happens, the trophy should pop.