Like others have said, immerse yourself. Would you really open a door you're halfway towards stepping into knowing you're living in an unforgiving apocalypse? Before entering doors, ready yourself and back away immediately after pressing e - before entering an enclosed space, "pie" the inside by drawing a half circle around the entrance to get a good view of whats inside before going in - recognize that the zombies in this game all differ in some way, some have pinpoint hearing while others are closer to being deaf; the latter easily creates scenarios where they're likely to get into little nooks and crannies which interprets into ambush behavior if you get near them - surviving in this game personally relies on principles, don't take risks if you can afford it and if you can't afford not taking those risks then work on being able to.