Go to the End and find a large void area
Build a spawning platform far from the main island
Use end stone or any solid block for the platform
Make the platform wide enough for Endermen to spawn
Place trapdoors or slabs to control spawning spaces if needed
Add a central hole or drop chute in the platform
Use water streams only if applicable outside the End; Endermen are immune to water damage but can be moved with careful design
Build a 3-block-high enclosed chamber to protect yourself from Endermen
Place an Endermite in a minecart as bait
Name the Endermite with a name tag so it does not despawn
Position the Endermite so Endermen can see it but cannot reach it
Use fences, glass, or slabs to keep the Endermite safe
Make Endermen fall into a killing chamber or drop shaft
Add a kill method such as a sword, trident killer, or fall damage setup
Add hoppers and chests to collect ender pearls and experience
Light up or remove nearby spawnable areas to improve rates
Stand at the correct AFK spot so Endermen spawn only in the farm
Test the farm and adjust platform size, bait position, and killing chamber as needed