Find a flat area and build a platform at least 16 blocks away from any other village beds, bells, or workstations
Place 20 beds in a compact village setup
Place 20 villagers and make sure each villager can claim a bed
Give each villager a workstation so they can work
Keep the villagers safe inside a sealed chamber
Add at least 3 zombie or other hostile mob scare setup so villagers panic
Make sure the villagers can see the hostile mob periodically
Build a spawning platform around the village center where iron golems can appear
Use water currents to push spawned iron golems into a kill chamber
Place lava or campfires in the kill chamber to damage the iron golems
Put hoppers under the kill chamber to collect iron ingots and poppies
Spawn-proof all nearby blocks so iron golems only spawn on the farm
Test that villagers sleep, work, and panic correctly
Wait for iron golems to spawn and check that the collection system works