The first way in which belief in afterlife influences Christians today is not to fear the death. They may believe that death is not the end. They know they are going to heaven which is a good place to go and will live with God without pain. "Their will be no more death, or mourning, or crying, or pain"
The second way in which belief in the afterlife influences Christians today is not to donate their organs after they die. They believe that God will bring them to resurrection, and therefore they want to have their full body during resurrection.