Spawn in the swamp biome in front of you. But in case of this seed we don’t talk about surface of it, because the most precious in found in the underground. From the spawn dig straight down like a picture below, you have enough material to craft tools. Keep digging straight down until you find the entrance of the cave. In there you can find 8 diamonds and more.
Seeds : -1881589003 Work in PE ver0.12.1 and ver0.11.0+