To get Unique items in Diablo 4, you can find them as random loot drops from enemies, quests, or chests. Defeating powerful bosses and elite enemies also increases your chances of obtaining them. Participating in world events and completing high-level dungeons improves your odds. Sometimes, Unique items may be available for purchase from in-game vendors or merchants. Additionally, engaging in seasonal events or special activities can offer opportunities to acquire Unique items.